EGHKIGAL  INSTRUCTION  SERIES 

r 


H    HP 

ES. 

Edited    by  P                             ^jjjjjjjlir 

lical  Instruction 

THE  LIBRARY 

House  Decc 

G,    PAINTING,   etc. 

With  79  I                                          OP 

Contents.  —  (                                            VxJ. 

,c.     Tools  used  by 

•ffibfi      THE  UNIVERSITY 

g.     Whitewashing 
Embellishment  of 

B;°'f  pi       OF  CALIFORNIA 

FINISHING.    With 
iocs.     Re-Welting 

±2s?i<2         LOS  ANGELES 

Stitching.     Making 

How  to  Writ 

;s  and  Diagrams. 

Contents.  —  T 

ignwriter's  Outfit. 

Making   Signl 
Shaded  and  I 

>rms  of  Lettering, 
ng.     Poster-Paint- 

ing.     Letterin                                       GIFT  OF 

Wood  Finish 
ings  and  . 

IG.    With  Engrav- 

Contents.  —  ] 

d.    French  Polish- 

wlx  FiniThin 
Stopping  or  B 

Off.     Glazing  and 
Reviving.     Hard 
Varnishing  Wood 

Varnishes.     E 

Dynamos  an 

ims. 

Contents.  —  1 

,nchester  Dynamo. 

Simplex   Dyn; 

Small   Dynamos. 

Ailments  of  S 

s.     Small  Electro- 

motors  withoi 

cation  of  a  Motor. 

How  to  Make 

amo.     Manchester 

Type  440-Watv  -j  

Cycle  Building  and  Repairing.     With  142  Engravings  and  Diagrams. 
Contents.  —  Introductory,  and  Tools  Used.     How  to  Build  a  Front  Driver.     Building  a 
Rear-driving  Safety.    Building  Tandem  Safeties.    Building  Front-driver  Tricycle.    Build- 
ing a  Hand  Tricycle.    Brazing.    How  to  Make  and  Fit  Gear  Cases.   Fittings  and  Accesso- 
ries.    Wheel  Making.     Tires  and  Methods  of  Fixing  them.     Enamelling.     Repairing. 

Decorative  Signs  of  All  Ages  for  All  Purposes.   With  277  Engravings  and  Diagrams. 
Contents.  —  Savage    Ornament.      Egyptian    Ornament.     Assyrian    Ornament.     Greek 

Ornament.  Roman  Ornament.  Early  Christian  Ornament.  Arabic  Ornament.  Celtic 
and  Scandinavian  Ornaments.  Mediaeval  Ornament.  Renascence  and  Modern  Orna- 
ments. Chinese  Ornament.  Persian  Ornament.  Indian  Ornament.  Japanese  Ornament. 
Mounting  and  Framing  Pictures.  With  240  Engravings,  etc. 

Contents.  —  Making  Picture  Frames.     Notes  on  Art  Frames.     Picture  Frame  Cramps. 
Making   Oxford   Frames.     Gilding  Picture   Frames.     Methods  of   Mounting   Pictures. 
Making  Photograph  Frames.     Frames  covered  with   Plush   and    Cork.     Hanging  and 
Packing  Pictures. 
Smiths'  Work.     With  211  Engravings  and  Diagrams. 

Contents.  —  Forges  and  Appliances.  Hand  Tools.  Drawing  Down  and  Up-setting. 
Welding  and  Punching.  Conditions  of  Work:  Principles  of  Formation.  Bending  and 
Ring  Making.  Miscellaneous  Examples  of  Forged  Work.  Cranks,  Model  Work,  and 
Die  Forging.  Home-made  Forges.  The  Manipulation  of  Steel  at  the  Forge. 


Glass  Working  by  Heat  and  Abrasion.     With  300  Engravings  and  Diagrams. 

Contents.  —  Appliances  used  in  Glass  Blowing.  Manipulating  Glass  Tubing.  Blowing 
Bulbs  and  Flasks.  Jointing  Tubes  to  Bulbs  forming  Thistle  Funnels,  etc.  Blowing  and 
Etching  Glass  Fancy  Articles;  Embossing  and  Gilding  Flat  Surfaces.  Utilising  Broken 
Glass  Apparatus;  Boring  Holes  in,  and  Riveting  Glass.  Hand-working  of  Telescope 
Specula.  Turning,  Chipping,  and  Grinding  Glass.  The  Manufacture  of  Glass. 


DAVID  McKAY,  Publisher,  Washington  Square,  Philadelphia. 


HANDICRAFT  SERIES   (Continued). 


Building  Model  Boats.     With  168  Engravings  and  Diagrams. 

Contents. — Building  Model  Yachts.     Rigging  and  Sailing  Model  Yachts.     Making  and 
Fitting  Simple  Model  Boats.     Building  a  Model  Atlantic  Liner.     Vertical  Engine  for  a 
Model  Launch.     Model  Launch  Engine  with  Reversing  Gear.     Making  a  Show  Case  for 
a  Model  Boat. 
Electric  Bells,  How  to  Make  and  Fit  Them.     With  162  Engravings  and  Diagrams. 

Contents. — The  Electric  Current  and  the  Laws  that  Govern  it.  Current  Conductors 
used  in  Electric-Bell  Work.  Wiring  for  Electric  Bells.  Elaborated  Systems  of  Wiring; 
Burglar  Alarms.  Batteries  for  Electric  Bells.  The  Construction  of  Electric  Bells,  Pushes, 
and  Switches.  Indicators  for  Electric-Bell  Systems. 

Bamboo  Work.     With  177  Engravings  and  Diagrams. 

Contents. — Bamboo:  Its  Sources  and  Uses.  How  to  Work  Bamboo.  Bamboo  Tables. 
Bamboo  Chairs  and  Seats.  Bamboo  Bedroom  Furniture.  Bamboo  Hall  Racks  and  Stands. 
Bamboo  Music  Racks.  Bamboo  Cabinets  and  Bookcases.  Bamboo  Window  Blinds. 
Miscellaneous  Articles  of  Bamboo.  Bamboo  Mail  Cart. 

Taxidermy.     With  108  Engravings  and  Diagrams. 

Contents. — Skinning  Birds.  Stuffing  and  Mounting  Birds.  Skinning  and  Stuffing 
Mammals.  Mounting  Animals'  Horned  Heads:  Polishing  and  Mounting  Horns.  Skin- 
ning, Stuffing,  and  Casting  Fish.  Preserving,  Cleaning,  and  Dyeing  Skins.  Preserving 
Insects,  and  Birds'  Eggs.  Cases  for  Mounting  Specimens. 

Tailoring.     With  180  Engravings  and  Diagrams. 

Contents. — Tailors'  Requisites  and  Methods  of  Stitching.  Simple  Repairs  and  Press- 
ing. Relining,  Repocketing,  and  Recollaring.  How  to  Cut  and  Make  Trousers.  How 
to  Cut  and  Make  Vests.  Cutting  and  Making  Lounge  and  Reefer  Jackets.  Cutting  and 
Making  Morning  and  Frock  Coats. 

Photographic  Cameras  and  Accessories.      Comprising  How  TO  MAKE  CAMERAS, 

DARK  SLIDES,  SHUTTERS,  and  STANDS.     With  160  Illustrations. 

Contents. — Photographic  Lenses  and  How  to  Test  them.  Modern  Half-plate  Cameras. 
Hand  and  Pocket  Cameras.  Ferrotype  Cameras.  Stereoscopic  Cameras.  Enlarging 
Cameras.  Dark  Slides.  Cinematograph  Management. 

Optical  Lanterns.     Comprising  THE  CONSTRUCTION  AND  MANAGEMENT  OF   OPTICAL 

LANTERNS  AND  THE  MAKING  OF  SLIDES.     With  160  Illustrations. 

Contents. — Single  Lanterns.  Dissolving  View  Lanterns.  Illuminant  for  Optical  Lan- 
terns. Optical  Lantern  Accessories.  Conducting  a  Lime-light  Lantern  Exhibition.  Ex- 
periments with  Optical  Lanterns.  Painting  Lantern  Slides.  Photographic  Lantern 
Slides.  Mechanical  Lantern  Slides.  Cinematograph  Management. 

Engraving  Metals.     With  Numerous  Illustrations. 

Contents. — Introduction  and  Terms  used.  Engravers'  Tools  and  their  Uses.  Ele- 
mentary Exercises  in  Engraving.  Engraving  Plate  and  Precious  Metals.  Engraving 
Monograms.  Transfer  Process  of  Engraving  Metals.  Engraving  Name  Plates.  En- 
graving Coffin  Plates.  Engraving  Steel  Plates.  Chasing  and  Embossing  Metals.  Etch- 
ing Metals. 

Basket  Work.     With  189  Illustrations. 

Contents. — Tools  and  Materials.  Simple  Baskets.  Grocer's  Square  Baskets.  Round 
Baskets.  Oval  Baskets.  Flat  Fruit  Baskets.  Wicker  Elbow  Chairs.  Basket  Bottle- 
casings.  Doctors'  and  Chemists'  Baskets.  Fancy  Basket  Work.  Sussex  Trug  Basket. 
Miscellaneous  Basket  Work.  Index. 

Bookbinding.     With  125  Engravings  and  Diagrams. 

Contents. — Bookbinders'  Appliances.  Folding  Printed  Book  Sheets.  Beating  ana 
Sewing.  Rounding,  Backing,  and  Cover  Cutting.  Cutting  Book  Edges.  Covering 
Books.  Cloth-bound  Books,  Pamphlets,  etc.  Account  Books,  Ledgers,  etc.  Coloring, 
Sprinkling,  and  Marbling  Book  Edges.  Marbling  Book  Papers.  Gilding  Book  Edges. 
Sprinkling  and  Tree  Marbling  Book  Covers.  Lettering,  Gilding,  and  Finishing  Book 
Covers.  Index. 

Bent  Iron  Work.     Including  ELEMENTARY  ART  METAL  WORK.     With  269  Engravings 
and  Diagrams. 

Contents. — Tools  and  Materials.  Bending  and  Working  Strip  Iron.  Simple  Exercises 
in  Bent  Iron.  Floral  Ornaments  for  Bent  Iron  Work.  Candlesticks.  Hall  Lanterns. 
Screens,  Grilles,  etc.  Table  Lamps.  Suspended  Lamps  and  Flower  Bowls.  Photo- 
graph Frames.  Newspaper  Rack.  Floor  Lamps.  Miscellaneous  Examples.  Index. 

Photography.     With  Numerous  Engravings  and  Diagrams. 

Contents. — The  Camera  and  its  Accessories.  The  Studio  and  the  Dark  Room.  Plates. 
Exposure.  Developing  and  Fixing  Negatives.  Intensification  and  Reduction  of  Nega- 
tives. Portraiture  and  Picture  Composition.  Flash-light  Photography.  Retouching 
Negatives.  Processes  of  Printing  from  Negatives.  Mounting  and  Finishing  Prints. 
Copying  and  Enlarging.  Stereoscopic  Photography,  Ferrotype  Photography. 

DAVID  McKAY,  Publisher,  Washington  Square,  Philadelphia. 


HANDICRAFT  SERIES  (Continue^. 


Upholstery.     With  162  Engravings  and  Diagrams. 

Contents.— Upholsterers'  Materials.  Upholsterers'  Tools  and  Appliances.  Webbing, 
Springing,  Stuffing,  and  Tufting.  Making  Seat  Cushions  and  Squabs.  Upholstering  an 
Easy  Chair.  Upholstering  Couches  and  Sofas.  Upholstering  Footstools,  Fenderettes, 
etc.  Miscellaneous  Upholstery.  Mattress  Making  and  Repairing.  Fancy  Upholstery. 
Renovating  and  Repairing  Upholstered  Furniture.  Planning  and  Laying  Carpets  and 
Linoleum.  Index. 

Leather  Working.     With  162  Engravings  and  Diagrams. 

Contents.— Qualities  and  Varieties  of  Leather.  Strap  Cutting  and  Making.  Letter 
Cases  and  Writing  Pads.  Hair  Brush  and  Collar  Cases.  Hat  Cases.  Banjo  and  Man- 
doline Cases.  Bags.  Portmanteaux  and  Travelling  Trunks.  Knapsacks  and  Satchels. 
Leather  Ornamentation.  Footballs.  Dyeing  Leather.  Miscellaneous  Examples  of 
Leather  Work.  Index. 

Harness  Making.    With  197  Engravings  and  Diagrams. 

Contents. — Harness  Makers'  Tools.  Harness  Makers'  Materials.  Simple  Exercises  in 
Stitching.  Looping.  Cart  Harness.  Cart  Collars.  Cart  Saddles.  Fore  Gear  and  Leader 
Harness.  Plough  Harness.  Bits,  Spurs,  Stirrups,  and  Harness  Furniture.  Van  and  Cab 
Harness.  Index. 

Saddlery.     With  99  Engravings  and  Diagrams. 

Contents.— Gentleman's  Riding  Saddle.  Panel  for  Gentleman's  Saddle.  Ladies'  Side 
Saddles.  Children's  Saddles  or  Pilches.  Saddle  Cruppers,  Breastplates,  and  other 
Accessories.  Riding  Bridles.  Breaking-down  Tackel.  Head  Collars.  Horse  Clothing. 
Knee-caps  and  Miscellaneous  Articles.  Repairing  Harness  and  Saddlery.  Re-lining 
Collars  and  Saddles.  Riding  and  Driving  Whips.  Superior  Set  of  Gig  Harness.  Index. 

Knotting  and  Splicing,  Ropes  and  Cordage.  With  208  Engravings  and  Diagrams. 
Contents. — Introduction.  Rope  Formation.  Simple  and  Useful  Knots.  Eye  Knots, 
Hitches  and  Bends.  Ring  Knots  and  Rope  Shortenings.  Ties  and  Lashings.  Fancy 
Knots.  Rope  Splicing.  Working  Cordage.  Hammock  Making.  Lashings  and  Ties  for 
Scaffolding.  Splicing  and  Socketing  Wire  Ropes.  Index. 

Beehives  and  Beekeepers'  Appliances.     With  155  Engravings  and  Diagrams. 

Contend.— Introduction.  A  Bar-Frame  Beehive.  Temporary  Beehive.  Tiering  Bar- 
Frame  Beehive.  The  "  W.  B.  C."  Beehive.  Furnishing  and  Stocking  a  Beehive.  Obser- 
vatory Beehive  for  Permanent  Use.  Observatory  Beehive  for  Temporary  Use.  Inspection 
Case  for  Beehives.  Hive  for  Rearing  Queen  Bees.  Super-Clearers.  Bee  Smoker. 
Honey  Extractors.  Wax  Extractors.  Beekeepers'  Miscellaneous  Appliances.  Index. 

Ready  Shortly : 

Electro  Plating. 

Other  Volumes  in  Preparation. 

DAVID  McKAY,  Publisher,  Washington  Square,  Philadelphia. 


PATTERN    MAKING 


WITH  NUMEROUS  ENGRAVINGS  AND  DIAGRAMS 


EDITED    BY 

PAUL     K    HASLUOK 

HONOURS  MEDALLIST  IN  TECHNOLOGY 
AUTHOR   OF   "HANDVBOOKS   FOR   HANDICRAFTS,"    ETC.    ETC. 


PHI  LA  DELPHI  A 
DAVID    McKAY,    PUBLISHER 

G10,    SOUTH    WASHINGTON  SQUARE 
1905 


L»r.ry 

TS 


PREFACE. 

PRACTICAL  PATTERN  MAKING  contains,  in  a  form  convenient 
for  everyday  use,  a  comprehensive  digest  of  information,  con- 
tributed by  experienced  craftsmen,  scattered  over  the  columns 
of  WORK,  one  of  the  weekly  journals  it  is  my  fortune  to  edit, 
and  supplies  concise  information  on  the  general  principles  and 
practice  of  the  art  on  which  it  treats. 

Readers  who  may  desire  additional  information  respecting 
special  details  of  the  matters  dealt  with  in  this  book,  or  in- 
structions on  any  kindred  subject,  should  address  a  question 
to  WORK,  so  that  it  may  be  answered  in  the  columns  of  that 
journal. 

P.  N.  HASLUCK. 

La  Belle  Sauvage,  London, 
September,  190?. 


F 

Ua 


cr 


733815 


CONTENTS. 

CHAPTER  PAGE 

I. — Foundry  Patterns  and  Foundry  Practice  ...      9 

II. — Jointing-up  Patterns 24 

III. — Finishing  Patterns 36 

IV.— Circular  Patterns 42 

V.— Making  Core-boxes 50 

VI.— Coring  Holes  in  Castings    .        ....        .        .59 

VII. — Patterns  and  Moulds  for  Iron  Columns    .        .        .83 
VIIL— Steam-engine  Cylinder  Patterns  and  Core-boxes     .    93 

IX.— Worm  Wheel  Pattern 101 

X.— Lathe-bed  Patterns      .        .        .        .        .        .        .110 

XI.— Headstock  and  Poppet  Patterns          .        .        .        .125 

X IF. —Slide-rest  Patterns 135 

XIII. — Miscellaneous  Patterns  and  Core-boxes    .        .        .147 
Index     ,  .  158 


LIST    OF    ILLUSTRATIONS. 


FIG.  PAGE 

1,  2.— Pegside    and   Eyeside   of 

Flask 12 

3,  4. — Square  Flask 


14 


5,  6.-Oblong  Flask 
7.— Flask    ready    for    Vertical 
Pouring  .... 

8.— Moulding  Board 
9,  10.— Clamp          .... 
11.— Moulding  Tub 
12-14.— Moulding  Trough       . 
15.— Section  of  Mould    . 
16. — Section  of  Trough  . 
17,  18. — Rammiag  Benches  . 
19.— Runners   in   Mould 

20.— Halving 

21,  22.— Middle      and      Dovetail 
Half-checks    .... 
23.— Dovetail     . 
24-26.— Three-part  Checks 
27-29. — Four-part  Checks 
30.— Section  of  Metal  Peg 
31,  32.— Metal  Plate  Dowe: 
33.— Round  Plate  Dowel 
34. — Cup  and  Peg  Dowel 
35.-Feather-edged   Fillet 
36,  37.— Angle-bo  ird 
38.— Inlaid    Fillets         .        .        .    .vt 
?9.— Inclined  Rib   .        .        .        .33 
40.— Leather    Strip    for    Curved 

Fillet 33 

41.— Fillet  Worked  out  of  Flange  33 
42-44.— Feather-edged  Fillets  .  34 
45.— Fillet  for  Core-box  with 

Loose  Ends     .        .        .        .34 
46,  47.— Fillets    Worked    out    of 

Solid 

48.— Iron  for  Searing  Plain  Sur- 
faces         

49._Searing  plain  Bolt  Holes  . 
50.— Searing     Holes    for    Cone- 
headed  Screws 

51. — Searing   Holes   for   Cheese- 
headed  Screws      . 
52.— Searing   Holes   in   Strainer 
Core-box         .... 
53. — Searing     Hole     of     Convex 
Section      from      Opposite 

Sides 

54.— Knob  Pattern  with  Chuck- 
ing Piece  .... 
55.— Undercut  Knob  Pattern  . 
56.— Correct  Shane  for  Pattern 
57.— Pillar  with  Chucking 

Pieces  at  Each  End  . 
5S.  59.— Ring  Casting      . 
60. — Template  for  Segments 
61.— Sawing-board  .... 
62.— Segments    Tightened    with 

Dog 

63.— Building  Pattern  of  Vary- 
ing Section  .... 
64. — Segments  built  up  on  Disc 
65.— Plate  for  Shaping  Pegs  . 
66. — Circular  Pan,  with  Cover  . 


25 
26 

.      26,  27 

.      27,  28 

Dowel  28 

.        .29 

.    29 

.    31 

.    31 

.    32 


FIG.  PAGfi 

67.— Axle  for  Strickle  ...  48 
63.— Strickling  Shell  ...  49 
69.— Edge  of  Strickle  ...  49 
70.— Core-box  for  Circular  Core  50 
71. — Half  of  Core-box,  showing 

Dowels  ....    51 

72.— Core-box  for  Bend-pipe     .    51 
73.— Template  for  Working  Cir- 
cular   Core-boxes       .        .    51 
74.— Working       out       Circular 

Core-box  with  Set-square  52 
75.— Fixing  Steel  Plate  in 

Corner  of  Set-square  .  52 
76.— Internal  Flange  fitted  into 

Core-box  .  .  .  .53 
77.-Chamber  Core  ...  53 
78.— Core-box  for  Chamber-core  54 
7?.— Core-box  witli  End  of 

Small  Diameter  .  .  54 
80,  81.— Rectangular  Core  «nd 

Core-box  ....  55 
82.— Built-up  Box  for  Large 

Rectangular  Core      .       .    56 
83.— Half    Box    for    Large    Cir- 
cular Core   .        .        .        .57 
84,  £5. — Symmetrical    and    Un- 

symmetrical  Cores  .  .  57 
E6.— Core  for  Bend-pipe  with 

Branch  ....  58 
87. — Core-box  for  Fly-wheel  .  58 
88,  89.— Cylinder  Cover  Casting  59 
90.— Cylinder  Cover  Pattern  .  60 
91,  92.— Core-box  for  Cylinder 

Cover 61 

91 — Mould  for  Cylinder  Cover.  61 
94,  95.-Casting  of  Engine 

Cylinder       ....    63 
96,  97.— Engine    Cylinder    Pat- 
tern         64 

93,  99.— Mould        for        Engine 

Cylinder  ....  65 
100-104.— So  uare  Prints  .  .  .  66 
105,  106.— Steam  Chest  Casting  .  67 
107-109.— Steam  Chest  Pattern  .  68 
110.— Mould  for  Steam  Chest  .  69 
111,  112.-Casting  of  Hand  Cap- 
stan Boss  .  .  .  .69 
113,  114.— Hand  Capstan  Boss 

Pattern          .        .        .        .70 
115,  116.— Mould  for  Hand  Cap- 
stan Boss      .        .        .        .70 
117,  118.— Bracket  Casting   .        .    71 
119,  123.— Bracket   Pattern  with 

Core  Prints  .  .  .  72 
12t.-F0ot  of  Bracket  Pattern  73 
122,  123.— Sections  through 

Cored  Mould  .  .  73,  74 
124,  121.— Core-box  for  Foot  of 

Bracket  ....  74 
126,  127.— Stopping-over  Board 

for  Cores       .        .        .        .75 
128,  129.— Bracket   Casting   .        .    76 
130,  131.— Bracket    Casting    Pat- 
tern with  Core  Prints    .    76 


Pit AC TIC A L  PATTERN  MAKING. 


FIG.  PAGE 

132,  133.— Alternative  Method  of 

Arranging  Pocket  Prints    77 
134,  135.— Pipe       Casting      with 

Square  Holes  in  Flanges    78 
136,  137.— Pattern  of  Flange  for 

Pipe  Casting  with  Prints    78 

138.— Mould    for    Pipe    Casting 

with  Cores  Inserted  .       .    79 

139,  140.— Stopping-over  Piece    .    79 

141,  142.— Bracket   Casting  with 

Slot  Holes  in-  Foot    .        .    80 

143.— Prints  on  Foot  of  Bracket 

Pattern          .        .        .        .80 

144.— Patterns  united  with  Con- 
tinuous Print  .  .  .80 

145,  146.— Double  Bracket  Cast- 
ing   81 

147,  148.— Double  Bracket  Pat- 
tern   82 

149-153.— Column  Pattern      .      84,  85 

154.— Drag  for  Casting  Columns  .    87 

155-157.— Mould  for  Column       87,  89 

153. — Pouring  Arrangements       .    89 

159.— Longitudinal     Section     of 

Small  Steam  Cylinder     .    94 

160,  161.— Cross  Sections  through 
Exhaust  Port  and  Steam 
Passage  .  .  .  .94 

162,  163.— Half  Pattern  of  Core- 
box  for  Cylinder  .  .  96 

164,  165.— Half     Body     Core-box 

for  Small  Steam  Cylinder    96 

166,  167.— Half  Core-box  for  Ex- 
haust Port  .  .  .  .96 

168-170.— Steam-chest  Core-box  .    97 

171,  172.— Steam-inlet  Core-box  .    93 

173-176.— Steam-port  Core-box     .    99 

177,  178.-Loose  Piece  for  Valve 

Spindle   Stuffing-box        .  100 

179,  180.— Half  Core-box  for 
Valve  Spindle  Stuffing- 
box  100 

181.— Worm  Wheel  Casting         .  101 

182,  183.-End  View  and  Section 

of  Worm  Wheel  Casting  .  102 

184.- Marking  Section  of  Worm 

Wheel 102 

185,  186.— Half  Pattern  of  Worm 
Wheel  Body  Glued  up 
Roughly  .  .  .  .103 

187,  188.— Jointing  Worm  Wheel 

Pattern          .        .        .        .105 

189.— Turning    Outside    of    Rim 

by  Template       .       .       .  105 

190.— Tooth  Block  Glued  on  Rim  106 

191. — Turning  Tooth   Points   by 

Template      .       .       .       .106 

192. — Turning  Inside  of  Rim  by 

Template      .       .       .       .106 

193.— Forms  of  Teeth  on  Worm 

Wheel 107 

194.— Template      for      Marking 

Tooth  Curves       .        .        .  107 

195.— Cutting  Wheel  Teeth  .        .  108 

196.-Worm  Wheel  Pattern        .  109 
».— Lathe-bod   Casting        .  110 


|     FIG.  PAGE 

200,  201.— Lathe-bed  Pattern        .  Ill 
I    202,  203.— Cross-bar  and  Foot  of 

Lathe-bed  Pattern     .       .  Ill 
204-211.— Gap  Lathe-bed  and  Pat- 
tern       .        .        .  114,  116.  113 
212.— Fitting  Bearers  with  Dove- 
tails        119 

213-223.— Core-boxes   for   Taking 
out      Portions      of      Gap 
Lathe-bed    .       .       .      120-123 
224-226.— Back-geared  Headstock 

Pattern  .  .  .  .126 
227.— Round  Parallel  Prints  .  127 
223.— Curved  Horns  for  Mandrel 

Bearings  ....  127 
229-234.— Headstock  Patterns  123,  129 
235,  236.— Plain  Square  Core-box  129 
237-239.— Lathe  Poppet  Pattern  .  130 
240,  241.— Moulding  Barrel  for 

Lathe  Poppet  .  .  .131 
242.— Barrel  for  Lathe  Poppet. 

with  Dowels  and  Hollows  131 
243.— Turning  Poppet  Barrel      .  131 
244  250.— Lathe       Poppet       Pat- 
tern      ....      132-134 
251-255.— Slide-rest    Saddle    Pat- 
tern       ....    136-139 
256,  257. — Core-box  to  Form  Re- 
cess for  Surfacing  Screw  139 
258,  259.— Core-box    for    Sliding 

Pinion  Spindle  .        .        .140 
230  262.— Surfacing      Slide     Pat- 
terns        140 

233,  264.— Ring       Core-box       for 

Surfacing  Slide  .  .  140 
265. — Core-box  to  Form  Recess 

for  Screw  ....  142 
266.— Half  Box  Opened  in  Joint 

Face 142 

267. — Transverse       Section       of 

Core-box  .  .  .  .142 
263-270.— Swivel  Slide  Pattern  .  143 
271,  272.— Top  Slide  Pattern  .  144 
273,  274.— Apron  Pattern  .  .  145 
275,  276. — Screw-down  Valve  .  148 
277.— Body  Pattern  for  Screw- 
down  Valve  .  .  .  .149 
278. — Core-box  for  Screw-down 

Valve 149 

279.— Valve  Top  Cap  Pattern      .  150 
280.— Core-box  for  Valve  Top  Cap  150 
281,  282.— Nut  Pattern  and  Core- 
box          151 

283.— Knob  Pattern  .  .  .151 
284.— Core-box  for  Knob  .  .  151 
235-287.— Globe  Valve  Core-box 

152,  153 

288.— Template  .  .  .  .153 
289,  290.— Turned  Segments  .  154 
291,  292.— Working  Segments  154 
293.— End  of  Segment  .  .  .155 
294,  295.— Block  for  Ends  of  Seg- 
ments   155 

296-298.— Bull-nose   Plane     .        .  156 
299,  300.— Core-box      for      Bull- 
nose   Plane          ,       ,       .157 


PRACTICAL 
PATTERN     MAKING. 

CHAPTER  I. 

FOUNDRY   PATTERNS  AND   FOUNDRY   PRACTICE. 

A  FOUNDRY  pattern  is  a  counterpart  of  a  casting,  and  is 
used  to  form  the  mould  into  which  the  molten  metal  is 
poured.  Pattern-making  is  thus  a  very  important  part  of 
foundry  work,  and  the  pattern-maker  must  be  a  craftsman 
of  experience  and  of  more  than  ordinary  intelligence. 
Pattern-making  is  done  usually  in  a  shop  having  only  two 
or  three  workmen,  each  one  of  whom  must  be  able  to  make 
any  description  of  pattern  that  may  be  wanted.  Thus  one 
man  soon  comes  to  command  a  wide  range  of  the  art,  and  is 
obliged  to  be  conversant  with  a  great  number  of  processes 
widely  different  in  character  the  one  from  the  other.  The 
competent  pattern  maker  has  a  knowledge  of  practical 
plane  and  solid  geometry  and  of  mechanical  drawing ;  he 
is  constantly  required  to  lay  upon  an  uneven  angular  sur- 
face lines  which  the  ordinary  draughtsman  can  get  much 
more  easily  on  the  smooth  surface  of  paper.  He  must 
know  the  nature  of  the  woods  or  other  material  used,  and 
be  able  to  construct  and  form  with  accuracy  any  con- 
ceivable shape  of  body,  so  that  it  will  best  stand  the 
strains  of  the  work  required,  and  keep  its  size.  He  must 
understand  how  the  pattern  can  best  be  moulded,  since 
he  is  required  to  decide  how  much  of  a  pattern  is  neces- 
sary, and  where  and  how  to  make  the  parting,  taper,  prints, 
core-boxes,  etc. 

The  object  of  a  pattern  being  to  facilitate  the  making 
of  a  mould,  the  pattern-maker  must  know  the  capacity  of 
the  moulder  and  his  appliances.  Some  moulds  can  be 
made  more  cheaply  without  a  pattern  by  the  use  of  strikes, 
others  with  a  combination  of  strikes  and  parts  of  pattern, 


10  PRACTICAL  PATTERN  MAKING. 

others  with  cores,  while  others  require  a  full  pattern  of 
the  size  and  shape  of  casting  required,  plus  the  allow- 
ance for  shrinkage.  Thus  a  pattern  may  be  made  to  cost 
more  in  the  pattern-making,  and  less  in  the  moulding,  or 
more  in  the  moulding,  and  less  in  the  pattern-making, 
according  to  which  workman  can  do  the  work  the  cheapest. 
The  number  of  castings  expected  to  be  made  will  also 
affect  the  construction  and  finish  of  a  pattern.  For 
instance,  if  twenty  castings  are  required  from  one  pattern, 
and  one  hour's  work  more  on  the  pattern  would  save  the 
moulder  five  minutes  on  each  mould,  there  would  be  an 
economy  of  forty  minutes  saved  by  the  extra  hour  spent 
in  pattern  work  ;  while  if  there  was  but  one  casting  to  be 
made,  and  the  one  hour's  pattern  work  was  still  put  upon 
it,  there  would  be  a  loss  of  fifty-five  minutes,  seeing  that 
the  moulder  was  saved  but  five  minutes'  work.  After  the 
pattern-maker  has  considered  all  the  requirements  of  the 
moulder,  he  must  follow  the  casting  in  his  mind  into  the 
machine  shop,  and  consider  the  shrinkage,  finish,  and  the 
ultimate  strength  and  soundness  of  the  parts. 

A  mould  is  an  impression  in  sand  shaped  to  correspond 
with  the  required  casting,  and  it  is  best  produced 
by  ramming  up  in  the  sand  a  pattern  or  model 
of  the  article  required.  This  pattern  must,  of  course, 
be  withdrawn  from  the  sand  before  the  mould  can 
receive  the  molten  metal,  and  the  pattern  must  therefore 
be  so  constructed  that  it  may  be  withdrawn  from  the 
sand  without  disturbing  the  mould.  The  non-appreciation 
of  this  essential  is  the  cause  of  frequent  indifferent  and 
useless  patterns  being  made.  The  first  important  point 
in  pattern-making  is  that  a  pattern  must  be  tapered  to 
allow  for  withdrawing  it  from  the  mould  (exceptions  will 
be  dealt  with  in  their  place).  A  well-tapered  pattern 
readily  "draws";  the  act  of  withdrawing  a  pattern  is 
known  as  the  "draft." 

Most  works  on  pattern-making  give  detailed  information 
on  the  many  varieties  of  woods  used,  describe' the  tools 
employed,  and  attempt  a  course  of  instruction  in  the  use 
of  both  materials  and  tools.  But  that  is  quite  outside  the 
present  scope,  and,  indeed,  is  quite  unnecessary  here. 
Pattern-making  is  such  an  intricate  craft  that  the  whole  of 
the  space  here  available  is  necessary  for  an  adequate  con- 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.  11 

sideration  of  the  methods  of  forming  the  patterns  them- 
selves. Detailed  information  on  tools  and  materials 
must  be  looked  for  elsewhere.  The  whole  subject  of  wood- 
working is  dealt  with  comprehensively  in  "  The  Handy- 
man's Book  of  Woodworking,"  a  book  of  760  pp.  produced 
under  the  direction  of  the  editor  of  this  work. 

Wood  for  pattern-making  should  be  well  seasoned,  and 
practically  all  kinds  are  in  use  for  the  purpose.  Large, 
long  and  flat  patterns  are  made  of  white  or  yellow  pine, 
on  account  of  its  lightness,  cheapness,  and  freedom  from 
warping  and  splitting,  but  it  has,  of  course,  the  other  dis- 
advantage of  being  soft  and  more  liable  to  receive  injury 
when  made  up.  Choice  Canadian  red  pine  is  harder,  but 
should  be  selected  as  free  from  knots  and  turpentine  as 
possible.  Still  harder  is  white  fir  (spruce  fir),  which  is 
admirable  for  large  wheel  patterns  ;  the  harder  the  wood, 
the  finer  does  it  look  when  sawn,  but  the  working  of  this 
material  is  troublesome  when  catfaced,  that  is,  when  some 
parts  are  smooth  and  some  rough.  Teak  is  light,  strong 
and  durable,  and  easily  worked,  but  punishes  the  tools  a 
little,  and  is  somewhat  liable  to  split.  Any  part  of  a 
pattern  which  has  to  be  turned  may  be  made  of  beech, 
which  has  a  uniform  grain.  Much  elm,  oak,  maple  and 
sycamore  is  used  also. 

For  small  patterns  the  Germans  use  cherry-tree  wood, 
well  seasoned,  because  it  is  hard  and  close  grained ;  but 
in  England,  mahogany  (chiefly  baywood)  comes  into  use 
for  small  work,  and  will  be  found  to  suit  nearly  all 
patterns  ;  it  warps  less  than  other  woods,  shrinks  but  little 
in  drying,  and  can  be  worked  at  the  ends  easily,  its 
corners  keeping  sharp  ;  but  the  tools  used  must  be  in  good 
condition.  Boxwood  also  is  an  excellent  wood  for  small 
patterns. 

A  very  important  point  in  pattern-making  is  the  duo 
allowance  for  shrinkage.  Castings  in  iron  vary  in  shrink- 
age, according  to  their  mass  ;  for.  metal  1  in.  in  thickness, 
allow  T^  in.  to  the  foot  in  making  the  pattern,  while 
thinner  castings  require  more,  and  thicker  a  shade  less 
allowance  in  proportion. 

Brass  shrinks  rather  more,  and  £  in.  may  be  substituted 
for  the  ^  in.  afore-mentioned.  For  castings  under  1  ft. 
long,  shrinkage  need  scarcely  be  taken  into  consideration  ; 


12  PRACTICAL  PATTERN  MAKING. 

the  rapping  of  the  pattern  by  the  moulder  usually  suffices. 
This  rapping,  which  is  done  to  loosen  the  pattern  before 
drawing,  is  usually  done  by  boring  a  hole  in  the  pattern, 
and  inserting  a  spike  in  the  same,  and  then  rapping  the 
spike  on  all  sides  with  a  hammer.  This  necessarily  tries 
the  strength  of  the  pattern,  and  if  many  castings  are 
required  off  one  pattern,  it  is  well  to  cut  a  small  mortise 
when  the  rapping  hole  is  wanted,  and  insert  therein  a 
small  iron  plate  with  a  hole  in  it,  thereby  saving  the  wood 
from  the  actual  contact  with  the  spike. 

In  making  patterns  of  articles  which  have  to  be  worked 
up  before  use,  it  is  well  to  allow  sufficient  metal  for  the 
process.  A  file  or  lathe  will  easily  remove  a  superfluous 


Fig.  1.  Fig.  2. 

Figs,.  1  and  2. — Peg-side  and  Eye-side  of  Flask. 

T'ff  in.,  but  no  mechanical  method  can  satisfactorily  add 
that  amount  if  it  be  lacking  at  the  first. 

Metal  patterns  are  used  when  a  large  supply  of  castings 
is  required.  Iron,  brass,  or  white  metal  is  commonly  used 
for  patterns.  Core-boxes  are  made  of  the  same  material 
as  patterns.  Iron  has  to  be  protected  from  rusting  by 
varnishing  or  beeswaxing  ;  brass  and  white  metal  do  not 
need  protection.  As  the  thickness  of  metal  is  often 
shaved  down  as  slight  as  possible,  plaster  of  Paris  is 
frequently  used  to  obtain  exact  thickness  before  casting 
the  final  pattern  or  core-box.  An  alloy  of  lead  and  tin 
is  also  used  for  patterns.  The  patterns  should  be  chased 
up  and  finished  to  the  very  finest  degree,  and  if  made  in 
two  or  more  parts  the  necessary  fitments  for  fixing  them 
should  be  soldered  on,  so  that  the  portions  when  cast  may 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.   13 

fit  together  easily.  Exact  making  and  finishing  of  the 
patterns  will  be  advantageous,  as  better  castings  will 
result,  and  the  fitter's  work  is  rendered  very  much  easier. 

An  outline  of  foundry  operations  will  now  be  given  to 
enable  the  worker  to  construct  patterns  intelligently,  and 
with  their  ultimate  use  well  in  mind. 

The  sand  moulds  into  which  the  molten  metal  is  poured 
are  made  in  flasks  or  moulding  frames.  These  consist  of 
a  pair  of  shallow  frames,  without  top  or  bottom,  and  usually 
made  of  cast-iron,  having  lugs  on  the  one  side  as  at  A 
(Fig.  1),  and  lugs  with  holes  in  on  the  other  side  as  B 
(Fig.  2).  Wooden  flasks  are  used  in  brass  foundries*, 


ife-.  3.  J?ig.  4. 

Figs.  3  and  4.— Plan  and  End  of  Square  Flask. 

though  they  are  seldom  seen  in  English  iron  foundries. 
The  fitting  of  the  pegs  and  the  eyes  of  each  pair  of  frames 
forming  a  moulding  box  must  be  very  exact,  so  that  there 
may  be  no  shifting.  In  the  pair  of  frames  forming  the  brass 
founder's  flask,  one  is  called  the  peg-side,  while  the  other 
is  the  eye-side.  In  iron  foundries  the  two  parts  are  called 
the  cope  and  drag,  and  these  are  fitted  with  lugs  having 
matching  pins  and  holes,  the  two  being  either  cottered 
together,  or  weighted  and  poured  while  laid  horizontal 
on  the  sand  floor.  There  is  one  type  of  brass  founder's 
flask,  however,  which  is  not  employed  by  the  iron  founder, 
that  in  which  the  mould  is  poured  while  the  flask  stands 
vertical,  or  in  a  slightly  sloping  position.  Figs.  3  and  4 


II 


PRACTICAL  PATTERN  MAKING. 


show  a  flask  used  by  brass  founders  and  iron  founders,  and 
made  in  sizes  from  about  9  in.  to  18  in.  square,  usually 
without  bars  or  stays.  Such  flasks  are  poured  while  laid 


\2/  \2/ 

Fig.  5.  Fig.  6. 

Figs.  5  and  0.— Plan  and  Section  of  Oblong  Flask, 
horizontal.     Figs.  5  to  7  show  the  type  of  flask  which  is 
used  for  vertical  pouring.     These  flasks  usually  are  jointed, 
and  have  pins  in  the  lugs. 

The  sand  is  contained  between  moulding  boards  (Fig.  8), 


Fig.  7. — Flask  ready  for  Vertical  Pouring. 

upon  which  the  flasks  are  rammed,  and  by  which  the 
mould  is  confined  during  pouring  by  means  of  clamps 
(Figs.  9  and  10).  The  boards  are  of  deal  or  oak,  and  the 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.  15 

ends  are  tongucd  to  prevent  warping.  They  are  from  1$  in. 
to  1|  in  thick.  Flasks  that  are  made  of  wood  are  strongly 
dovetailed  or  tenoned,  and  clamped  at  the  corners,  and 


Fig-.  8.— Moulding  Board. 

the  top  end,  which  is  pierced  with  holes,  is  made  of  iron, 
or  protected  with  iron. 

A  flask  made  wholly  of  iron  costs  rather  more  in  the 
first  place  than  a  wood  flask,  but  it  is  practically  ever- 
lasting, besides  being  more  rigid.  In  Figs.  5  and  6  a 
rib  is  shown  cast  round  the  edges  of  the  flasks  next  the 
faces,  against  which  the  boards  are  clamped.  In  some 
American  flasks  the  section  is  grooved  in  order  to  confine 


Fig.  10. 
Figs.  9  and  10.— Side  and  Edge  Views  of  Clamp. 

the  sand  more  efficiently.     The  clamps  are  of  wood,  and 
so  are  the  screw  nuts  shown  in  Figs.  9  and  10. 

In  brass  foundries  the  moulding  tub  to  contain  the  sand 


16 


PRACTICAL  PATTERN  MAKING. 


usually  consists  of  an  iron  casting  about  6  ft.  long,  2  ft. 
wide  at  the  bottom,  and  about  2  ft.  3  in.  at  the  top  by 
15  in.  deep.  This  is  placed  on  brick  supports,  one  at  each 
end,  so  that  its  top  edge  is  about  2  ft.  3  in.  from  the  floor 
(see  Fig.  11).  In  smaller  foundries  very  frequently  the 
work  bench  is  made  a  part  of  the  moulding  tub,  the 
advantage  being  that  the  sand  is  handy  in  the  tub  beneath 
the  bench,  which  forms  the  cover  of  the  tub.  When  a 
plain  bench  is  employed,  the  sand  is  brought  in  small 
quantities  from  the  sand  bins  or  tubs,  and  placed  in  a 
small  heap  at  the  back  of  the  bench.  The  moulding 
trough  of  the  brass  founder  is  shown  by  Figs.  12,  13,  and 
14,  which  illustrate  a  plan,  side  elevation,  and  end  eleva- 
tion ;  this  tub  affords  at  once  a  receptacle  for  sand  and 


.  11.—  Moulding  Tub. 


a  work  bench.  It  stands  against  the  wall,  and  is  about 
2  ft.  6  in.  high  and  wide,  and  of  any  length.  The  tub 
shown  is  for  one  man,  the  work  being  done  upon  the  sliding 
board  A,  beneath  which  is  the  trough,  which  contains  the 
sand.  The  trough  is  made  of  deal  of  about  ij  in.  thick, 
dovetailed  or  nailed  at  the  corners,  and  tapered  at  front 
and  sides  for  convenience  of  shovelling  out  the  sand. 

When  preparing  a  mould  the  sand  is  first  tempered  by 
the  addition  of  water,  and  passed  through  a  sieve  of  about 
five  or  six  meshes  to  the  linear  inch.  Raw  sand  must  be 
employed,  as  used  or  burnt  sand  does  not  possess  the 
adhesiveness  necessary  for  the  purpose,  since  it  contains 
proportions  of  charcoal  and  other  substances,  such  as 
peaflour,  brickdust,  etc.  The  sharp  edges  of  the  sand 
grains  too  have  been  rounded  by  use  ;  they  cannot,  there- 
fore, wedge  together  so  firmly. 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.  17 


The  moulding  of  the  odd-side  is  begun  by  taking  an 
eye-side  frame,  and  placing  it  on  a  board.  The  inside  of 
this  frame  is  dusted  over  with  parting  sand,  and  then  the 
side  is  filled  with  black  sand,  to  which  some  raw  sand  has 
been  added.  This  is  rammed  down  tight,  first  with  the 


palms  of  the  hands,  then  with  the  knuckles,  and,  lastly, 
with  a  wooden  mallet ;  occasionally  the  workman  will 
tread  it  down  firmly  as  the  final  operation.  The  sand  is 
then  scraped  level  with  a  bar  of  iron,  a  moulding  board 
is  laid  on  the  top,  and  the  frame  with  its  entire  contents 
is  inverted. 

The  patterns  to  be  moulded  are  now  laid  very  carefully 


18  PRACTICAL  PATTERN  MAKING. 

on  the  face  of  the  mould,  and  the  dust  bag  shaken  over 
them ;  this  leaves  on  the  sand  a  clear  outline  of  the 
patterns.  These  are  now  lifted  off,  and  the  sand  is  care- 
fully cut  away,  leaving  the  patterns  embedded  half-way. 

A  peg-side  frame,  to  fit  on  the  odd-side,  is  placed  on  the 
eye-side,  as  illustrated  by  the  sectional  view  (Fig.  15),  and 
then  parting  sand  is  dusted  over  the  sand,  a  mixture  of 
raw  and  black  sand  is  laid  over  the  half  embedded 
patterns,  and  the  mould  filled  with  black  sand.  The 
whole  of  the  sand  in  the  flask  is  now  carefully  rammed 
as  tight  as  possible,  as  described  above.  A  second  mould- 
ing board  is  placed  on  the  top  of  the  flask  and  well 
hammered  to  loosen  the  patterns,  and  the  whole  is  turned 
over  and  again  hammered.  The  patterns  will  now  be  in 
the  eye-side,  which  is  ready  for  moulding  from.  Fig.  16 
shows  a  moulding  trough  in  section  in  which  the  flask 
is  supported  on  boards  that  may  be  shifted  along. 


Fig.  15.— Section  of  Mould. 

For  making  the  peg-side  mould,  the  process  is  repeated, 
a  peg-side  frame  is  placed  on  the  eye-side,  sand  pressed 
in  as  before,  covered  by  a  board,  and  the  whole  inverted. 
The  patterns  are  loosened  by  hammering  on  the  top  board, 
and  the  odd  peg-side,  which  now  bears  perfect  impressions 
of  one-half  of  each  pattern  in  the  flask,  is  taken  off, 
leaving  the  patterns  in  the  eye-side.  The  frame  called  the 
peg-side  is  now  taken  and  placed  on  the  eye-side,  sand  is 
placed  in  the  mould  and  well  rammed,  as  in  previous 
operations ;  the  peg-side  is  removed,  leaving  the  patterns 
in  the  eye-side ;  the  odd-side  is  brought  and  placed  on 
the  eye-side,  and  the  whole  inverted.  The  patterns  are 
loosened  by  hammering,  the  eye-side  is  taken  away,  and, 
the  patterns  being  left  in  the  odd  peg-side,  all  is  ready  for 
use  again,  and  thus  the  odd-side  can  be  repeatedly  used 
for  moulding  purposes. 

In  many  cases  where  large  quantities  of  castings  of 
similar  work  are  (required,  there  are  two  other  methods 
adopted  in  moulding,  namely,  platework  and  gatework. 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.  19 

These  methods  are  excellent,  and  might  be  adopted  with 
advantage  to  a  much  greater  extent.  They  are  suitable 
for  use  either  in  hand  moulding  or  in  conjunction  with  a 
moulding  machine.  The  chief  advantage  of  machine- 
over  hand-moulding  is  that  a  perpendicular  lift  is  ensured, 
thus  diminishing  the  risk  of  the  breaking  down  of  sand  in  a 
deep  face. 

In  platework  the  patterns  are  attached  to  a  match 
plate  or  board,  while  in  gatework  a  number  of  patterns 
sufficient  to  fill  the  standard  flask  are  riveted  or  soldered 
to  the  gate-piece,  practically  forming  one  pattern. 
Platework  and  gatework  have  each  their  own  merits,  but 
generally  it  is  better  to  put  the  patterns  on  plates  than 


Fig.  16.— Section  of  Trough. 

to  gates,  whenever  it  is  possible  to  do  so.  Bib-cocks, 
plugs,  handles,  stems,  globe  and  other  valves,  the  parting 
lines  of  which  are  straight,  can  all  be  made  on  the  plate 
principle,  thereby  saving  the  time  that  would  be  expended 
in  making  odd-sides,  trimming  the  joints  of  the  mould,  etc., 
necessary  with  gated  patterns. 

There  are  several  kinds  of  plated  patterns,  the  methods 
of  moulding  being  different  in  certain  cases.  The  simplest 
plated  work  is  that  in  which  two  portions  of  a  pattern 
are  put  on  opposite  sides  of  a  plate,  wood  being  employed. 
The  two  portions  of  the  pattern  are  precisely  like  those 
which  would  be  used  if  there  were  no  plate  interposed, 
these  portions  being  those  which  go  into  the  opposite 
halves  of  the  flask,  the  thickness  of  the  plate  being 


20  PRACTICAL  PATTERN  MAKING. 

immaterial.  In  moulding,  the  two  sides  of  a  flask  are 
rammed  on  opposite  sides  of  the  plate,  being  cottered 
together  through  it,  and  the  flasks  being  turned  over  for 
the  ramming  of  opposite  sides. 

A  superior  and  more  permanent  pattern  plate  is  made 
of  iron  or  brass.  In  this  the  opposite  portions  of  the 
pattern  are  prepared  as  though  for  moulding  in  the 
ordinary  way,  and  then  they  are  screwed  to  the  opposite 
sides  of  a  metal  plate  about  f  in.  or  \  in.  in  thickness, 
and  the  flasks  are  rammed  from  the  opposite  sides  of  the 
pattern.  In  another  method  the  two  halves  of  a  pattern 
are  moulded  on  a  separate  plate  instead  of  on  opposite 
sides  of  the  same  one,  and  the  flasks  are  rammed  apart, 
and  are  only  brought  together  when  being  closed  for 
pouring.  In  this  method  also  wood  and  metal  plates  are 
both  used.  Each  of  these  types  of  plates  is  used  either 
with  flasks  rammed  in  the  usual  way  or  upon  a  moulding 
machine.  Interchangeable  flasks  are  almost  a  necessity 
in  platework,  as  the  plate  must  fit  on  the  peg-sides  of 
flasks,  which  are  thus  used  as  dowels. 

The  advantages  and  disadvantages  of  platework  and 
odd-side  moulding  may  be  summarised.  Patterns  once  put 
on  a  plate  are  only  suitable  for  using  in  groups,  while 
patterns  moulded  in  an  odd-side  can  be  made  in  any 
groupings.  This  latter  is  a  great  advantage,  when  the 
numbers  required  off  given  patterns  vary  from  time  to 
time ;  work  put  on  plates  should  be  arranged  so  that 
sets  shall  be  completed  without  any  parts  being  in  excess 
on  the  one  hand,  or  insufficient  in  numbers  on  the  other. 
To  mount  metal  patterns  on  plates  is  costly,  and  is  only 
economical  when  large  quantities  of  castings  are  wanted. 
The  fitting  must  be  done  most  accurately,  otherwise  there 
Avill  be  lapping  joints  and  cores  out  of  truth.  Small  brass 
work  can  only  be  done  cheaply  and  well  by  the  adoption 
of  odd-side  or  plate  moulding,  and  the  choice  must  be 
controlled  by  circumstances.  When  the  platework  or 
gatework  method  is  adopted,  the  advantages  are  that  the 
time  of  bedding  a  pattern  temporarily  into  its  cope,  and 
of  making  the  joint  face  and  sloping  joints  on  which  to 
ram  the  drag,  is  wholly  saved.  The  time  in  cutting 
runners  is  also  saved.  These  occupy  a  good  deal  of  time 
when  a  number  of  patterns  are  moulded  in  one  flask,  and 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.  21 


especially  when  they  are  of  shapes  involving  the  making 
of  numerous  sloping  and  curved  down-joints.  These 
methods  of  moulding  are  generally  practicable  when  doing 
a  large  run  of  standard  work,  but  they  are  seldom  avail- 
able in  small  foundries,  and  therefore  the  odd-side  method 
is  generally  preferred  in  these. 

The  sand  floor  usual  in  a  foundry  is  useful  for  bedding 
the  heavier  work,  which  is  covered  with  copes.  It  is  also 
used  to  lay  the  flasks  upon  when  moulded  and  prepared 
ready  for  casting.  As  the  sand  is  receiving  constant 
additions  from  the  new  sand  used  in  facings,  a  depth  of 
from  3  in.  to  6  in.  will  be  sufficient  to  lay  down  at  starting. 
It  is  employed  over  and  over  again  for  box  filling,  re- 


Fig-.  17. — Ramming  Bench 
Bolted  to  Wall. 


Fig.  18.— Ramming  Bench 
Supported  by  Legs. 


serving  the  new  special  sand  for  facings — that  is  to  say, 
for  the  stratum  of  sand  which  is  immediately  next  the 
pattern  to  a  thickness  ranging  from  £  in.  to  1  in.,  hence 
called  pattern  facings.  In  the  smallest  moulds  facing  sand 
alone  would  be  employed.  Partings  for  brass  moulds  are 
made  of  burnt  red  sand  or  of  red  brickdust.  Peameal 
dusted  over  is  used  for  facing  green  sand  work,  both 
light  and  heavy.  So  are  flour,  powdered  chalk,  whiting, 
and  sometimes  charcoal.  Lime  mixed  with  water  is  used 
for  facing  dry  sand  moulds  and  cores  for  brasswork. 

In  a  small  foundry  it  is  necessary  to  have  a  bench,  on 
which  moulds  except  those  occasionally  made  in  the  sand 
floor  will  be  rammed.  The  bench  will  be  of  dimensions  most 
suitable  to  the  work  required.  It  may  be  of  iron,  but 


22  PRACTICAL  PATTERN  MAKING. 

wood  is  suitable,  3-in.  deals  being  supported  on  wood 
brackets,  the  latter  being,  if  practicable,  bolted  to  the 
wall  with  through  bolts  and  wall  plates,  as  shown  in 
Fig.  17.  If  this  cannot  be  done,  the  support  may  be 
afforded  in  the  manner  illustrated  in  Fig.  18.  Three  11-in. 
or  9-in.  deals  will  afford  sufficient  width  of  bench  for  the 
average  run  of  brass  founders'  work. 

When  moulding  a  large  number  of  small  patterns  in  a 
single  flask,  they,  with  their  runners,  must  be  so  arranged 
that  the  metal  shall  not  cool  before  the  moulds  farthest 
from  the  ingate  are  reached.  To  this  end  it  is  desirable 
to  maintain  something  like  uniformity  in  size  and  mass 
of  the  several  patterns  included  in  any  one  flask  ;  to  have 


Fig.  It). — Arrangement  of  Runners  in  Mould. 

the  runners  of  sufficient  area ;  and  to  pour  the  metal 
sufficiently  hot  to  ensure  its  running  to  the  farther  end  of 
the  mould.  There  are  two  general  arrangements  of 
runners.  In  the  one  they  pass  from  mould  to  mould  in  a 
flask,  the  metal  running  through  the  successive  moulds  to 
the  last  one.  The  other  is  that  in  which  the  metal  (runs 
down  a  ridge  runner,  and  passes  thence  through  sprays 
to  the  moulds  arranged  on  one  side,  or  on  both  sides,  to 
right  and  left. 

A  ridge  of  large  area  and  small  sprays  is  the  ideal 
arrangement.  This  is  shown  in  Fig.  19.  The  patterns  are 
so  arranged  in  a  flask  that  during  the  pouring  some 
amount  of  pressure  is  imparted  by  a  head  of  metal. 
Generally,  this  takes  the  form  of  a  continuation  of  the 
head  of  the  ingate  a  few  inches  above  the  front  or  top 


FOUNDRY  PATTERNS  AND  FOUNDRY  PRACTICE.  23 

mould.  The  more  dense  the  metal  is  required  the  deeper 
must  this  head  be.  Castings  for  hydraulic  work,  which 
have  to  stand  test  pressures  of  1,000  Ib.  or  more  to  the 
inch,  have  to  be  very  dense.  If  sufficient  head  is  given 
above  the  mould,  it  is  not  necessary  to  cast  supplementary 
heads  upon  the  castings  themselves.  Such  heads  are 
sometimes  cast  on  the  ends  of  pump  liners  and  other 
cylindrical  work ;  but  that  is  more  with  a  view  to  take 
the  sullage  which  gathers  in  a  deep  mould. 

Before  the  moulds  are  finally  closed,  channels  must  be 
cut  in  them  connecting  the  various  small  impressions  with 
the  runners  and  gates,  in  order  to  convey  the  molten 
metal  to  the  necessary  parts  of  the  moulds.  A  very  good 
way  of  making  the  main  ingate  or  git-hole  is  to  procure  a 
thin  piece  of  tinplate  tubing,  and  with  it  cut  a  hole 
through  the  sand  in  the  top  box  to  the  parting,  after- 
wards withdrawing  the  tube  and  tapering  off  the  mouth  or 
top  part  of  the  hole  to  a  trumpet  or  bell  shape,  and  form- 
ing also  a  small  air-hole  from  the  top  box,  at  the  other 
end,  through  to  the  parting.  This  allows  the  escape  of 
the  gases  which  generate  within  the  mould  whilst  the 
metal  is  being  poured,  and  prevents  the  casting  turning 
out  blown,  or  damaged  by  small  holes.  The  channels 
must  be  sufficiently  large  to  allow  the  metal  completely 
to  fill  the  impression  made  in  the  mould,  but  must  not 
be  larger,  or  waste  of  metal  will  result.  It  is  usual  to 
put  the  runners  or  channels  in  the  eye-side,  while  if  any 
cores  are  used  they  are  placed  in  the  peg-side. 

The  moulds,  even  in  common  work,  are  usually  dried 
a  little  by  placing  before  a  stove  fire,  although  this  is 
not  absolutely  necessary  if  the  impressions  have  been 
carefully  prepared  and  dusted  with  charcoal,  it  must  not 
be  omitted  if  fine  castings  are  required.  If  both  sides  of 
the  casting  be  required  fine,  both  sides  of  the  mould  must 
be  dried.  When  sufficient  moulds  have  been  made  to  con- 
stitute a  heat — say  five  or  six — they  are  placed  against  the 
spilling  trough,  and  are  then  ready  to  receive  the  molten 
metal. 

Other  details  of  foundry  work  necessary  to  the  proper 
understanding  of  the  craft  of  the  pattern  maker  will  be 
given  as  occasion  demands. 


24 


CHAPTER  II. 


JOINTING-UP     PATTERNS. 

THE  halving  joint  is  largely  used  in  pattern-making,  and 
the  method  of  joining  two  pieces  of  wood  together  by  this 
means  is  apparent  from  Fig.  20.  In  making  this  joint, 
mark  one  side  of  each  of  the  pieces  to  be  joined  to 
indicate  the  face  side.  Set  a  gauge  to  half  the  thickness 
of  the  stuff,  and  gauge  lines  on  the  edges  where  the 
pieces  are  to  be  placed.  Always  gauge  from  the  face  side, 
so  that  even  if  the  gauge  was  not  set  exactly  to  half  the 
thickness  the  joint  will  still  come  even.  Screw  the  pieces 
together,  and  then,  if  the  fit  is  good,  take  them  apart, 
put  on  glue,  and  screw  them  together  again  while  the 
glue  is  hot. 


Fig.  20.— Halving. 

Corner  half-checks  are  generally  cut  the  whole  width 
of  the  stuff,  as  in  Fig.  20,  but  for  middle  pieces  the  check 
is  sometimes  made  short,  so  as  to  leave  a  portion  of  the 
timber  the  full  thickness,  adding  thereby  to  the  strength 
of  the  frame,  as  in  Fig.  21. 

The  dovetail  half-check  is  shown  in  Figs.  22  and  23  ; 
its  use  is  not  to  hold  the  pieces  together  (the  glue  and 
screws  do  that)  but  to  enable  a  portion  of  the  frame  to 
be  hollowed  out,  and  yet  not  reduce  the  cross-grained 
parts  (where  the  pieces  butt  together)  so  much  as  to  make 
them  weak  and  brittle. 

The  ordinary  half-check  answers  this  purpose  also,  pro- 


JOINTING-HP  PATTERNS.  25 

vided  the  tongue  and  the  space  which  it  fits  be  narrower 
than  the  stuff  is  wide. 

Other  joints  used  in  pattern-making  are  the  simple 
butt  joint  and  mitre.  Wheel  patterns  necessitate  some 
joints  that  are  out  of  the  common. 


Fig.  21.— Middle  Half -check. 

The  three-part  check  (Figs.  24  to  26)  is  used  for  wheels 
with  six  arms,  it  allows  three  pieces  to  be  joined  together 
in  the  thickness  of  one.  To  make  it,  find  the  centre  in 
each  of  the  three  pieces ;  with  a  radius  equal  to  half  the 
width  of  a  piece,  describe  a  circle  on  one  side  of  the  top 
and  bottom  pieces,  and  on  both  sides  of  the  middle  piece. 
Set  a  bevel  to  60°,  and  with  it  draw  lines  touching  the 
circles,  as  shown  in  the  figures.  Divide,  by  gauge  lines, 
the  thickness  of  the  pieces  into  three  equal  parts.  Let 
all  the  portions  of  the  pieces  be  cut  away  as  shown.  The 
middle  piece  is  to  be  cut  in  on  both  sides  as  illustrated, 


Fig.  22.— Dovetail  Half-check. 

leaving  one-third  part  in  the  centre.  Cut  away  the  top 
piece  at  the  part  represented  by  the  cross  shading  for  a 
depth  of  two-thirds  of  the  thickness. 

The  four-part  check  (Figs.  27  and  28)  is  the  joint  used 
for  making   an   eight-arm  wheel.     As   before,   circles   are 


26  PRACTICAL  PATTERN  MAKING. 

described  on  one  side  of  the  pieces  shown  by  Figs.  27  and 
29,  and  on  both  sides  of  that  shown  by  Fig.  28.  With  a 
bevel  set  to  45°,  draw  lines  touching  the  circles.  Three- 


Fig.  23.— Dovetail. 

quarters  of  the  thickness  of  the  piece  shown  by  Fig.  27 
must  be  cut  away  as  illustrated.  The  two  middle  pieces 
are  exactly  alike  on  one  side.  The  part  cross-shaded  must 


Fig.  24.— Three-part  Check. 

be  cut  down  to  half  the  thickness  ;  the  little  corners  and 
the  other  side  are  cut  down  for  a  quarter  thickness.  The 
cross-shaded  part  shown  in  Fig.  29  is  cut  down  for  three- 


Fig.  25.— Three-part  Check. 

quarters    of    the    thickness ;    the    corners    shown    lightly 
shaded  are  cut  down  one-quarter  only. 

In  the  construction   of  patterns,   glue   should  be  used 


J01NTING-UP  PATTERNS.  27 

as  little  as  possible.     It  frequently  swells  out  when  the 
damp   sand  comes  into  contact  with  it,   and  a  glued-up 


Fig.  26.— Three-part  Check. 


pattern  which  possibly  has  taken  hours  to  prepare  often 
comes  to  pieces  almost  the  first  time  of  using.  As  far  as 
possible  use  joiners'  brads,  or,  better  still,  slender  steel 


Fig.  27.— Four-part  Check. 

"wood"  screws.  When,  however,  glue  is  necessary,  only 
the  very  best  should  be  used ;  have  it  thin  and  fresh.  A 
little  quick-drying  linseed  oil,  well  stirred  in  while  the  glue  is 


.  28.—  Four-part  Check. 


quite  hot,  increases  its  resistance  to  moisture  ;  but  even 
then  a  coat  or  two  of  a  good  oil  paint  is  necessary  to 
protect  the  joint  from  the  moisture  arising  from  the  sand. 


28  PRACTICAL  PATTERN  MAKING. 

It  is  frequently  desirable  to  make  a  foundry'  pattern 
or  a  core-box  in  two  parts,  so  that,  while  one  part  cannot 
slide  upon  the  other,  it  may  readily  be  lifted  at  right 
angles  to  the  joint.  This  end  is  attained  by  the  use  of 
dowels. 


Fig.  29.— Four-part  Check. 

The  most  elementary  form  of  dowelling  consists  of 
circular  wooden  pegs  fitted  into  holes  bored  with  a  centre- 
bit.  If  the  depth  of  each  half  pattern  is  not  considerable, 
the  pieces  may  be  clamped  together,  and  a  hole  bored 
through  the  top  and  partly  into  the  lower  piece.  A  hard- 
wood peg  is  driven  through  the  top  half  until  it  protrudes 
from  %  in.  to  f  in.  ;  the  projecting  part  is  then  slightly 
tapered  towards  the  end,  so  that  it  is  free  from  the  hole 
immediately  it  is  lifted.  Of  course,  a  dowel  should  fit  so 
that  no  perceptible  lateral  motion  shall  be  possible. 

For  permanent  patterns,  malleable  cast-iron  dowels, 
such  as  are  shown  in  section  by  Figs.  30  and  31,  and  in  plan 
by  Fig.  32,  are  generally  used.  These  consist  of  pairs  of 
plates,  one  (in  Fig.  30)  carrying  a  turned  peg,  the  other 


Fig.  30.— Section  of  Metal  Peg  Dowel. 

(Figs.  31  and  32)  having  a  hole  into  which  the  peg  easily 
fits.  Each  has  countersunk  holes  for  the  screws  which 
fasten  it  to  the  core-box  or  pattern.  The  upper  plate  has 
two  or  more  sharpened  projections,  usually  at  the  corners 
of  the  plate  (see  Fig.  30). 


JOINTING-  UP  PA  TTERNS. 


The  plate  dowel  (Figs.  31  and  32)  being  laid  in  position, 
its  outline  is  scribed  upon  the  wood.  The  plate  is  then 
removed,  a  hole  bored  in  the  centre  of  the  space  marked, 
and  a  recess  cut  so  that  the  top  surface  of  the  plate  when 
fastened  down  sinks  slightly  below  that  of  the  wood.  The 


©O© 


Fig.  32. 


Figs.  31  and  32.— Sections  of  Metal  Plate  Dowel. 

peg  dowel  is  then  placed  in  position,  the  other  half  of  the 
pattern  is  laid  upon  it,  and  a  sharp  blow  struck  upon  the 
wood.  The  projecting  spikes  therefore  fix  the  position  of 
the  peg  dowel,  which  may  then  be  inserted  and  fastened 
as  before. 

Usually,  at  least  two  pairs  of  dowels  are  required,  and 
in  many  cases  more ;  in  such  circumstances,  if  misplaced 
in  the  least  degree,  the  dow-els  may  bind,  or  even  refuse 
to  enter  the  holes  when  the  two  parts  of  the  pattern  are 
brought  together.  This  may  sometimes  be  remedied  by 
a  sharp  lateral  blow  upon  one  of  the  dowelled  pieces  of 
wood  when  they  have  been  forced  together. 


©O®, 


Fig.  33.—  Hound  Plate  Dowel. 

To  find  out  where  the  binding  takes  place,  smear  the 
sides  of  the  hole  with  red-lead  and  oil ;  the  peg  is  then 
forced  into  it  by  a  blow,  and,  on  examination,  shows  where 
the  red-lead  has  adhered.  The  dowel  is  then  moved  to 
relieve  that  part. 


30  PRACTICAL  PATTERN  MAKING. 

Some  workmen  insert  all  the  plate  dowels,  then  lay 
in  place  all  the  peg  dowels,  and  mark  them  at  one  blow  ; 
but  it  is  better  to  mark  and  insert  the  peg  dowels  one  by 
one,  as  then  any  inaccuracy  may  be  detected  and  corrected 
as  it  arises.  Dowels  of  this  type  are  sometimes  made  of 
stamped  brass,  but  are  of  little  service  if  the  pattern  is 
roughly  or  frequently  used.  Dowels  of  the  shape  shown 
in  Fig.  33  may  be  let  into  the  wood  by  making  centre-bit 
holes  of  the  same  diameter  as  the  circular  parts  of  the 
plate,  spikes  on  the  bottom  of  the  plate  marking  the 
centres  required.  Small  patterns  sometimes  have  brass 
dowels  as  shown  in  Fig.  34. 

The  peg  carries  a  short  stem  on  which  depressions  are 
turned  to  lock  into  the  wood.  In  a  better  kind  the  stem 
is  screwed,  and  a  slot  at  the  end  of  the  peg  enables  it  to 
be  inserted  with  a  screwdriver.  Rings  are  also  turned  on 
the  outside  of  the  ferrule  or  socket.  To  insert  these 
dowels  a  hole  is  bored,  into  which  the  cup  dowel  may  be 
driven  tight,  but  just  before  it  is  driven  home  the  other 
piece  is  laid  over  it,  and  receives  a  blow  which  imprints 
upon  it  the  shape  of  the  projecting  part  of  the  cup  dowel. 
The  latter  may  now  be  completely  driven  home,  and  the 
peg  inserted  in  the  centre  of  the  circle  thus  marked. 

An  alternative  method  is  to  place  between  the  surfaces 
household  pins  whose  heads  'occupy  the  places  selected 
for  the  centres  of  the  dowels.  A  sharp  blow  presses  the 
head  of  each  pin  into  both  pieces  of  wood,  and  marks 
the  centres  for  the  boring  tools. 

.  The  joint  face  of  each  half  of  a  pattern  should  have 
screwed  upon  it  a  stout  rapping  plate  of  wrought-  or 
malleable  cast-iron,  having  two  holes,  one  tapped  for  a 
lifting  screw,  the  other  clear  for  a  rod  by  which  the 
moulder  loosens  the  pattern  in  the  sand  preparatory  to 
withdrawing  it.  The  top  of  these  plates  should  be,  say, 
-/g  in.  lower  than  the  surface  of  the  wood,  as  the  rapping 
burrs  the  edges  of  the  hole.  If  the  pattern  is  small 
enough  to  be  lifted  by  one  hand,  the  lifting  hole  should 
be  vertically  above  the  centre  of  gravity  of  the  pattern. 
This  point  may  be  found  experimentally  by  driving  in  a 
bradawl  and  suspending  the  pattern  in  the  hand. 

When  screws  are  used  to  connect  parts  of  a  pattern, 
their  heads  must  be  made  flush,  particularly  where  they 


JOINT1NG-UP  PATTERNS. 


31 


would  slide  upon  the  sand  during  the  lift.  If  the 
thickness  of  the  wood  through  which  the  shank  of  the 
screw  passes  is  not  less  than  |  in.,  the  neatest  method  is 
to  make  a  centre-bit  hole  and  sink  the  head  of  the  screw 
below  the  surface.  Wooden  plugs  are  then  glued  in  and 
cut  off  flush.  With  thin  stuff  the  holes  are  countersunk, 
the  screw  head  being  very  slightly  below  the  surface ; 
this  depression,  with  the  slot  in  screw  head,  is  filled 
with  ordinary  putty.  A  paste  made  of  whiting  and  shellac 
varnish  hardens  quickly,  but  when  mixed  it  must  be  used 
at  once. 

Wrhen  angles  in  a  casting  are  left  square,  the  strength 
of  the   casting   is   much   less   than   when   filled   in   with   a 


Fig.  35.— Feather-edged  Fillet. 


Fig.  34.— Cup  and  Peg  Dowel. 

curved  fillet.  This  is  due  to  the  crystallisation  of  cast-iron 
when  cooling.  The  tendency  of  the  crystals  to  form  with 
their  axes  at  right  angles  to  the  cooling  surface  of  the 
mould  causes  a  weak  junction  between  the  two  sets  of 
crystals  when  two  parts  of  a  casting  are  inclined  to  each 
other.  The  introduction  of  the  fillet  gets  rid  of  this  weak- 
ness. Moreover,  the  additional  metal  is  an  advantage  at 
the  angle  where  the  regular  formation  of  crystals  is  inter- 
fered with.  Practically  it  is  an  advantage  to  the  moulder 
by  relieving  him  of  a  fragile  salient  angle  of  sand. 

For  straight  lengths  of  filleting,  the  usual  practice  of 
the  pattern  maker  is  to  plane  strips  of  wood  to  a  triangular 
section,  which  are  then  hollowed  out  with  a  round-soled 
plane,  as  in  Fig.  35.  This  is  termed  "feather-edged" 


32 


PRACTICAL  PATTERN  MAKING. 


filleting,  or  "angling."  If  the  angle  A  is  slightly  more 
obtuse  than  a  right  angle,  the  fillet  will  fit  close  to  the 
corner  and  reduce  the  tendency  of  the  edges  to  curl  up. 
Moreover,  the  angle  in  the  pattern  is  seldom  or  never 


Fig.  36.  Fig.  37. 

Figs.  36  and  37.— Angle-board  for  Planing  Filleting. 

square  itself  owing  to  the  necessity  of  tapering  for  with- 
drawal from  the  sand. 

Figs.  36  and  37  show  section  and  side  elevation  of  an 
angle-board  which  is  used  for  planing  the  filleting.  Two 
chamfered  strips  are  fixed  together ;  a  stop  of  hardwood 
A  is  dovetailed  in  at  the  front  end,  and  toward  the  real 
a  cross  saw-cut  B  is  made  for  convenience  in  cutting  off 
lengths.  The  bottom  edge  is  recessed  for  working  smaller 
sizes. 

With  feather-edged  filleting  it  is  impossible  to  finish 
off  the  edges  to  a  curve  tangential  to  the  adjoining  sur- 


Fi?.  3S.— Inlaid  Fillets. 

faces,  for  this  would  mean  working  sharp,  fragile  edges. 
In  patterns  of  the  most  perfect  finish  and  durability, 
fillets  may  be  inlaid  as  in  Fig.  38.  This  form  would  be 
desirable  in  such  a  case  as  is  shown  at  A  (Fig.  39),  for  a 


JOINTING-UP  PATTERNS. 


33 


feather-edged  fillet  here  would  be  at  once  fragile  and 
clumsy.  In  this  case  the  fillets  are  of  different  curvature, 
the  most  shapely  finish  being  obtained  by  taking  tangents 
at  the  same  height  above  the  horizontal  part. 


Fig.  39. -Inclined  Rib. 


.  40.— Leather  Strip  for 
Curved  Fillet. 


When  one  or  both  of  the  adjoining  surfaces  to  be 
filled  in  are  of  a  curvature  to  which  a  straight  fillet  cannot 
readily  be  bent,  a  strip  of  leather  of  section  shown  by 
Fig.  40  is  soaked  in  water  to  make  it  pliable,  glued,  and 
then  pressed  in  with  a  short  stick  of  wood  turned  with 
a  rounded  end ;  or  a  strip  of  soft  metal  rolled  to  the 
required  section  is  pressed  in,  and  cemented  with  a  solu- 
tion of  shellac.  Such  sections  are  supplied  by  dealers  in 
pattern-makers'  requisites. 


Fig.  41.— Fillet  Worked  Out  of  Flange. 

In  some  cases  it  is  desirable  to  work  fillets  out  of  the 
solid,  and  one  such  instance  is  shown  in  Fig.  41.  Here, 
the  additional  base  given  to  the  shallow  flange  is  of  great 
advantage  in  fastening  the  parts  together,  without  adding 


34  PRACTICAL  PATTERN  MAKING. 

greatly  to  the  work — assuming,  of  course,  that  the  flange 
is  curved  in  plan.  If  the  work  is  built  in  segments,  the 
bottom  segment  may  be  made  wider,  to  allow  for  working 
the  fillet. 

A  cheaper  expedient  for  curved  work  is  to  fill  in  the 


Fig.  42. 


Fig?.  42  ani  4:^.— Strong  Form  of  Feather-edged  Fillet. 

space  with  a  mixture  of  beeswax  and  resin.  This  cement 
is  melted  and  brought  to  shape  with  a  heated  iron,  having 
one  end  shaped  a  half-round.  Occasionally  beeswax 
alone  is  used,  but  generally  it  is  too  soft. 


Fig.  44.— Weak  Form  of  Feather- 
edged  Fillet. 


Fig.  4.r>.— Fillet  for  Core-box 
with  Loose  Ends. 


The  strength  of  feather-edged  filleting  depends  greatly 
upon  the  disposition  of  the  grain  of  the  wood.  In  Figs.  42 
and  43,  for  instance,  it  is  arranged  in  the  most  advan- 
tageous manner,  whilst  in  Fig.  44  the  shortness  of  the 
grain  would  render  it  so  weak  as  to  be  useless  in  a 


JOIXTING-UP  PATTERNS. 


35 


pattern,  even  if  it  could  be  worked  successfully.  In  such 
cases  it  should  invariably  be  let  into  the  lower  piece. 

In  Fig.  45  is  shown  a  combination  of  feather-edged  and 
inserted  filleting,  used  when  one  p#rt  of  the  core-box  or 
pattern  is  not  permanently  attached  to  the  other. 

Sometimes,  as  in  small  brass  fittings,  the  angles  may 
best  be  worked  out  of  the  solid,  as,  for  instance,  in  the 


Fig.  4G.  Fig.  47. 

Figs.  46  and  47.— Fillets  Worked  out  of  Solid. 

guide  blocks  in  Figs.  46  and  47.  If  the  pattern  is  formed 
of  two  pieces  jointed  in  the  plane  A  B  (Fig.  47),  the  two 
may  be  taken  apart,  and  c,  being  worked  straight  through, 
its  shape  is  scribed  upon  D,  and  the  small  pockets  in  that 
piece  are  cut  out  with  carving  gouge  and  chisels. 

About  half  the  thickness  of  the  metal  is  usually  suffi- 
cient for  the  radius  of  a  fillet ;  if  it  is  too  great,  metal  will 
be  concentrated  so  much  as  to  draw  or  become  spongy.  . 


36 
CHAPTER  III. 

FINISHING  PATTERNS. 

A  PATTERN  that  has  been  brought  to  a  curved  shape  by 
chisel  and  gouge  must  be  glasspapered  afterwards  to  re- 
move the  marks  of  the  tool ;  in  planed  work  it  is  best  dis- 
pensed with.  In  ordinary  work  No.  2  paper,  followed  by 
No.  l£  or  No.  1,  will  be  found  most  useful.  All  tool  work 
should  be  done  before  glasspapering,  or  the  part  so  treated 
will  probably  be  soiled  by  handling  before  the  other  part 
is  ready,  and  the  tools  will  probably  be  dulled  by  particles 
of  grit.  Sharp  edges  should  be  rounded  off,  and,  if  not 
already  done,  angles  filled  in  with  curved  fillets. 

A  coat  of  varnish  prevents  a  foundry  pattern  absorb- 
ing moisture  from  the  damp  moulding  sand.  The  varnish 
is  made  by  dissolving  shellac  in  methylated  spirit,  and 
is  applied  with  a  camel-hair  brush.  When  the  first  coat 
has  dried,  the  surface  will  be  found  to  be  roughened  by 
the  raising  of  the  grain  of  the  wood.  It  must  be  rubbed 
down  with  a  piece  of  used  glasspaper,  and  another  coat 
of  varnish  applied.  After  this,  lightly  rub  down  again 
and  apply  a  third  coat. 

Red-lead  is  sometimes  put  in  the  varnish  to  give  more 
body  to  it,  and  to  fill  the  pores  of  the  wood  more 
thoroughly.  Whilst  the  pattern  body  is  thus  coloured  yel- 
low or  red  by  the  varnish  used,  core  prints  and  parts  on 
which  loose  pieces  are  to  be  wired  are  rendered  con- 
spicuous by  varnish  to  which  lampblack  has  been  added. 
Further,  to  inform  the  moulder  of  the  shape,  the  section 
should  be  hatched  on  the  joint  face  on  one  half  of  the 
pattern  with  another  coloured  varnish. 

Patterns  should  be  stamped  with  a  number,  and  all 
loose  parts  should  also  have  a  similar  number  to  show  the 
pattern  to  which  they  belong,  and  in  addition  a  distinguish- 
ing mark,  to  be  repeated  on  the  pattern  near  the  position 
of  the  piece.  A  number  of  loose  pieces  belonging  to  one 
pattern  may  be  kept  together  by  threading  on  wire  passed 
through  small  holes  bored  in  the  pieces. 


FINISHING  PATTERNS.  37 

Searing  signifies  the  smoothing  and  hardening  of  the 
surfaces,  or  portions  of  the  surfaces,  of  wooden  patterns 
in  order  to  render  them  more  easy  to  draw,  and  better 
able  to  resist  the  action  of  moisture  in  moulding  sand. 
It  may  be  used  with  or  without  an  after  protective  appli- 
cation of  shellac  varnish.  Searing  is  used  for  rough  work 
as  being  more  rapid  of  accomplishment  than  the  action 
cf  cutting  tools  and  of  glasspaper,  and  it  is  adopted  also 
in  certain  sections  of  good  work  to  produce  uniformity  and 
precision  of  results  which  could  not  well  be  obtained  in  any 
other  way. 

There  is  one  application  of  searing  which  consists  in 
going  over  large  flat  surfaces  with  a  hot  flat  iron.  Many 
years  ago,  the  flat  surfaces  of  large  patterns  were  quite  corn- 


Fig.  48.— Iron  for  Searing  Plain  Surfaces, 

monly  seared  or  scorched  in  order  to  smooth  and  harden 
their  surfaces,  and  so  assist  their  delivery  from  the  sand. 
The  old  millwrights  and  the  early  pattern  makers  did 
not  use  shellac  varnish  to  anything  like  the  extent  to 
which  it  is  employed  in  the  modern  shops.  It  was  re- 
served chiefly  for  the  smaller  patterns,  and  so  much  pains 
was  not  taken  with  patterns  then  as  now.  Standard  pat- 
terns now  in  shops  doing  repetitive  work  are  got  up  al- 
most regardless  of  cost.  And  it  pays  to  do  so.  In  a  few 
of  the  very  best  shops  the  wood  patterns  are  almost  like 
cabinet  work,  and  the  iron  ones  as  good  as  high-class 
fitters'  work.  The  millwrights  made  their  patterns  more  in 
the  style  of  country  carpentry,  accurate  enough  for  the  pur- 
poses for  which  they  were  wanted,  and  mouldable,  but 
with  no  attempt  at  finish,  often  not  even  glasspapered,  and 


oS 


PRACTICAL  PATTERN 


often  without  any  provision  for  rapping  and  lifting.    Those 
were  the  days  when  searing  irons  were  employed. 

The  irons  used  were  of  the  shape  shown  in  Fig.  48, 
differing  only  in  dimensions.  An  average  size  for  the  flat 
portion  was  about  5  in.  by  3  in.  by  1  in.  Some  were  shorter 
and  narrower,  some  wider.  They  were  brought  to  a  low 
red  heat  in  a  clear  fire,  the  face  just  rubbed  over  with  a 


Fig.  50.— Searing  Holes  for 
Cone-headed  Screws. 


Fig-.  49.— Searing  Plain  Bolt  Holes. 


file,  and  then  the  surface  of  the  pattern  was  seared  with 
the  broad  face.  A  quick  man  could  go  over  a  reasonably 
large  pattern  at  one  or  two  heatings  of  the  iron.  It  was 
just  a  light  skinning,  not  a  charring  of  the  wood.  It 
closed  and  smoothed  the  grain,  obliterated  plane  marks, 
and  gave  a  variegated  brown  and  white  appearance  to  the 
surface.  Glasspapering  was  not  necessary  either  before 


FINISHING  PATTERNS.  39 

or  after,  and  the  pattern  so  treated  came  from  the  sand 
freely. 

The  method  was  only  applicable  to  plain  surfaces.  The 
iron  could  not  be  worked  round  into  corners  or  concave 
parts,  but  such  parts  would  be  glasspapered  or  left  rough 
from  the  tools.  Searing  was  very  well  adapted  to  large 


Fig.  51.— Searingr  Hole  for          Fig.  52.— Searing  Holes  in  Strainer 
Cheese-headed  Screw.  Core-box. 

plain  patterns,  saving  the  cost  of  varnishing  or  painting, 
and  leaving  for  all  practical  purposes  as  good  a  surface. 
It  did  not  protect  the  grain  from  the  warping  effects  of 
moisture  so  well  as  paint  or  varnish,  but  that  is  seldom 
considered  of  much  account  in  large  plain  patterns,  which 
are,  in  fact,  often  broken  up  after  use. 

The  method,  however,  survives  in  another  way.     Holes 
for  self-delivery  are  seared  in  this  manner  more  rapidly 


40  PEACTIGAL  PATTERN  MAKING. 

and  quite  as  efficiently  as  by  glasspapering.  In  thin  cast- 
ings for  which  holes  are  cast  for  black  bolts,  or  for  cheese- 
head  or  cone-head  screws,  the  holes  are  often  made  to 
deliver  themselves  in  the  sand  instead  of  being  cored  out 
with  prints.  The  holes  which  are  cast  in  pipe  strainers, 
though  cored,  are  not  inserted  in  print  impressions.  In 
these  cases,  therefore,  the  searing  iron  is  used.  Figs.  49 


Fig.  53. — Searing  Hole  of|ConvexJSection  from  Opposite  Sides. 

to  52  illustrate  the  shapes  of  iron  of  this  class.  Fig.  49 
shows  one  used  for  plain  bolt  holes.  The  amount  of  taper 
given  to  it  is  just  sufficient  to  permit  of  free  delivery  in 
the  moulded  holes.  The  effect  of  a  slight  amount  of 
taper  in  much  black  fitting  work  is  of  no  consequence. 
In  the  holes  for  cone-headed  screws  (Fig.  50)  the  correct 
form  is  obtained  much  more  truly  and  cleanly  than  by 
the  use  of  cores,  and  with  a  far  less  expenditure  of  time 


FINISHING  PATTERNS.  41 

and  trouble.  Holes  for  cheese-headed  screws  (Fig.  51)' 
would  be  very  troublesome  to  form  accurately  without 
the  burning  iron.  When  many  holes  have  to  be  seared 
in  a  strainer  core-box  (Fig.  52)  they  can  be  done  uniformly 
and  quickly.  Fig.  53  shows  some  work  in  which  the  hole 
has  to  be  seared  from  opposite  sides. 

These  searing  irons  are  made  of  wrought-iron  or  steel, 
and  the  burning  ends  are  turned  to  correct  form.  If  not 
overheated  they  will  last  for  years.  The  handles  are  from 
18  in.  to  2  ft.  long. 

When  cutting  holes  which  afterwards  have  to  be  seared, 
it  is  not  necessary  to  observe  such  exactness  of  form  as 
when  they  are  finished  by  glasspapering  and  varnishing. 
The  holes  are  bored  small  enough  with  a  centre-bit ;  that 
is  sufficient  when  the  form  of  the  hole  is,  as  in  Fig.  49, 
just  plain  tapered.  When  it  is  of  any  of  the  forms  shown 
by  Figs.  50  to  53,  it  must  be  cut  nearly  to  shape  and 
dimensions  with  a  gouge.  The  burning  out  of  a  parallel 
hole  to  form  a  considerable  taper  would  char  the  timber 
too  deeply ;  the  art  of  searing  consists  in  just  burning  the 
mere  surface  to  a  brown  or  a  brownish-black  tint.  The 
iron  must  not  be  too  hot,  and  a  contact  of  a  second  or  two 
is  sufficient.  It  is  not  necessary  to  do  anything  further 
previous  to  moulding,  but  the  application  of  a  coat  or  two 
of  varnish  to  patterns  or  core-boxes  for  repetition  use  pre- 
vents the  roughening  up  which  results  from  frequent 
moulding 


4-2 
CHAPTER  IV. 

CIRCULAR    PATTERNS. 

IN  describing  a  pattern  to  be  used  for  making  a  mould, 
it  will  be  well  to  begin  with  one  of  the  simplest  kind. 
Fig.  54  shows  a  knob  to  be  turned  up  in  the  lathe  ;  it  is  not 
given  as  a  model  design,  because  a  pattern  made  to  the 
exact  shape  shown  is  almost  sure  to  give  trouble.  The 
hollow  part  A  has  parallel  sides,  and  lumps  of  sand  will 
remain  in  the  hollow,  with  the  result  that  corresponding 
lumps  will  be  found  on  the  castings.  Sometimes  patterns 
are  made  of  the  shape  indicated  in  Fig.  55 — that  is,  with 
the  hollow  undercut — and  such  a  pattern  will  not  leave  the 
sand.  The  proper  shape  is  given  in  Fig.  56 ;  there  it  will 


Fig.  54.— Knob  Pattern  Fip.  55.— Undercut  Fig.  56.— Correct  Shape 
with  Chucking  Piece.  Knob  Pattern.  for  Knob  Pattern. 

be  seen  that  all  surfaces  are  sufficiently  inclined  to  allow 
the  pattern  to  be  taken  out  of  the  mould  without  clogging 
the  sand. 

When  about  to  make  such  a  pattern,  first  decide  as  to 
size,  and  then  as  to  the  quantity  of  castings  likely  to  be 
required.  If  a  great  number,  make  the  pattern  in  brass  ; 
if  only  a  few  the  usual  method  is  to  make  it  in  boxwood. 
Beech  is  much  used  for  large  turned  patterns,  but  for  the 
present  requirements  is  useless. 

The  pattern  may  be  turned  in  the  lathe  with  ordinary 
turning  tools,  and  smoothed  with  fine  glasspaper,  a  good 
finish  being  got  by  taking  a  handful  of  clean  box  turnings 


CIRCULAR  PATTERNS.  43 

and  holding  these  against  the  pattern  whilst  the  lathe  is 
run  at  a  good  speed  A  boxwood  turned  pattern  finished  in 
this  way  has  a  surface  that  is  practically  perfect,  and  will 
not  need  varnishing,  etc.  When  making  patterns  of  castings 
to  be  finished  in  the  lathe,  it  must  be  decided  beforehand 
how  they  are  to  be  held  for  turning.  The  knob  here  shown 
will  need  something  by  which  to  hold  it,  and  the  plain 
projecting  piece  shown  at  the  top  of  Fig.  54  should  be 
left  on  for  the  purpose  of  chucking  it.  A  screw  can  then 
be  cut  on  the  foot,  or  it  can  be  drilled  and  tapped  without 
removal  from  the  lathe. 

From  such  a  pattern  as  the  one  just  described,  it  will 
be  but  a  step  to  the  making  of  spindles  and  more  orna- 
mental work,  but  if  these  are  of  considerable  length,  as 
Fig.  57,  they  must  be  supported  at  both  ends  in  turning. 
This  is  accomplished  by  leaving  on  the  dotted  portions, 


Fig.  57.— Pillar  with  Chucking  Pieces  at  Each  End. 

and  one  end  is  held  in  a  chuck  on  the  lathe,  while  the 
other  end  is  supported  by  the  back-centre. 

Segments  are  chiefly  used  by  the  pattern-maker  in  the 
construction  of  circular  patterns  that  are  to  be  turned 
to  shape  on  a  face-plate,  such  as  the  rim  of  a  wheel, 
a  piston,  ring,  etc.  Assuming  that  a  casting  has  to  be 
made,  such  as  Figs.  58  and  59,  first  prepare  a  template  of 
the  required  segment  from  thin  stuff  (Fig.  60).  The  space 
between  the  dotted  lines  and  the  outline  is  an  allowance 
of  J  in.  to  J  in.  for  turning  the  pattern  and  jointing  the 
ends.  The  pattern  for  a  turned  casting  has  an  extra 
|  in.  on  each  turned  surface.  The  smallest  patterns 
usually  have  four  segments  to  the  circle,  whilst  larger 
ones  have  six  or  eight ;  only  very  large  patterns  have 
more.  The  number  of  segments  that  can  be  cut  out  of 
the  width  of  a  board  is  next  ascertained,  and  the  length 
of  material  required  is  computed.  The  thickness  of  wood 
for  ordinary  work  is  from  f  in.  to  £  in.  For  very  slight 
and  fragile  work,  the  thickness  is  from  i  in.  to  |  in. 


44  PRACTICAL  PATTERN  MAKING. 

If  the  segments  are  small,  say  less  than  12  in.  long, 
the  wood  may  be  cut  into  convenient  lengths  for  planing, 
and  each  piece  faced  perfectly  flat.  The  template  may 
then  be  used  as  a  guide  in  marking  out  the  segments  on 
the  face  of  the  board.  A  band-saw,  bow-saw,  or  compass- 


Fig.  58.  Fig.  59. 

Figs.  58  and  59.— Ring  Casting. 

saw  may  be  used  for  cutting  out  the  segments,  and  a 
wooden  face-plate  is  next  mounted  on  the  lathe  as  a  foun- 
dation for  building  upon.  To  trim  the  ends  radially,  if  a 
small  allowance  only  has  been  left,  hold  the  segment  on  a 
shooting-board  and  shoot  the  ends  with  a  trying-plane. 

For  making  similar  segments,  the  sawing-board  (Fig.  61) 
will  be  an  aid.  On  a  rectangular  piece  of  board  D,  about 
1  in.  thick,  are  screwed  two  blocks  E  and  F,  each  having 


Fig.  6  . — Template  for  Segments. 

a  thickness  slightly  less  than  the  depth  of  a  tenon-saw 
blade.  H  is  a  template  about  f  in.  thick,  one  edge,  butting 
against  E,  being  planed  parallel  to  a  tangent  of  the  circle 
of  the  segment  where  it  is  cut  by  the  line  B  c,  and  recessed 
so  that  the  segment  A,  when  brought  against  it,  has  bearing 


CIRCULAR  PATTERNS. 


45 


points  at  the  ends  only.  In  the  line  B  c,  and  perpendicular 
to  the  base  board,  a  tenon-saw  cut  is  made  through  E  and  F 
to  form  a  guide  for  the  saw.  Beneath  the  base  at  the 
front  edge  a  strip  is  screwed,  which,  being  gripped  in  the 
vice,  keeps  the  appliance  steady  when  in  use.  After  one 


Fig.  61.— Sawing-board. 

end  of  each  segment  has  been  sawn  off  true,  another  piece 
of  wood,  shown  dotted  at  G,  is  fixed  above  the  template  to 
form  a  stop  when  the  segments  are  reversed  to  have  their 
other  ends  sawn  off ;  the  radial  line  to  which  this  is  set 
should  be  marked  on  when  the  template  is  set  out.  In 
setting  out  the  template  H,  the  radius  at  the  bearing  places 
is  that  to  which  the  segment  is  sawn.  Generally,  the 
ends  can  thus  be  left  true  enough  to  joint  together,  and 


Fig.  62.— Segments  Tightened  with  Dog. 

even  when  shooting  is  required  only  a  small  quantity  has 
to  be  taken  off. 

If  the  segments  are  large  and  the  work  heavy,  each  one 
of  the  first  course  may  be  screwed  from  the  back  of  the 
face-plate,  but  in  many  cases  it  is  sufficient  to  glue  paper  on 


46  PRACTICAL  PATTERN  MAKING. 

the  face-plate,  and  upon  this  the  segments  are  glued.  A 
pattern  of  considerable  diameter  and  little  depth  may  be 
held  by  a  patch  of  glue  at  each  end  of  a  segment.  The 
joints  are  drawn  together  with  dogs,  as  shown  in  Fig.  62. 
When  the  work  is  finished  a  chisel  is  used  as  a  wedge  to 
split  the  paper  and  detach  the  work  from  the  face  plate. 

A  quicker  way  is  to  nail  all  the  first  course  on  the  plate 
with  fine  oval  wire  nails  (well  punched  in),  and  when  the 
work  is  finished  wrench  it  off  with  a  chisel  as  before.  The 
nails  are  then  pulled  through  the  work  and  remain  in  the 
plate,  or  if  found  to  remain  in  the  work  may  afterwards  be 
pulled  through  with  pincers. 

The  first  course  is  faced  flat  in  the  lathe,  and  the  outside 
and  inside  are  turned  down  nearly  to  size.  The  next 
course  is  permanently  fixed  in  place,  each  segment  having 


Fig.  G3. — Building  Pattern  of  Varying  Section. 

its  centre  immediately  over  the  joint  between  the  segments 
in  the  course  below  it  (see  Fig.  62).  These  operations  are 
repeated  until  the  pattern  is  built  up,  after  which  it  is 
turned  to  shape  and  finished. 

For  a  casting  of  varying  section  (Fig.  63),  make  each 
course  of  segments  to  a  diameter  obtained  by  setting  out 
a  full-size  section.  The  courses  and  segments  should  be 
numbered.  When  the  section  varies  slightly,  several 
courses  may  be  sawn  of  the  same  diameter.  At  a  flange 
the  segments  should  be  so  thick  that  the  greater  part  (at 
least)  of  the  adjoining  fillet  may  be  formed  from  them. 
When  segments  are  to  be  built  up  on  a  wooden  disc,  as  in 
the  pattern  shown  at  Fig.  64,  a  rebate  is  turned  round  the 
edge  of  the  flat  disc  to  form  a  bed  for  the  segments. 
The  segments  are  brought  to  a  joint  at  A  by  means  of 
spokeshave  or  compass-plane. 


CIRCULAR  PATTERNS.  47 

The  joints  between  the  courses  are  glued,  and  further 
secured  by  screws,  nails,  or  pegs.  For  straightforward, 
substantial  work  screws  are  best,  the  heads  being  well  let 
in  to  avoid  the  turning  tools.  For  slighter  work  nails,  well 


Fig.   64.— Segments  Built  up  on  Difc. 

punched  down,  will  answer,  but,  when  the  contour  of  the 
pattern  is  curved  or  tapered,  it  is  best  to  use  wooden  pegs. 

Fig.  65  shows  a  steel  plate  for  making  the  pegs  circular 
after  they  have  been  split  off.  The  central  hole  has  a 
cutting  edge  slightly  below  the  face  of  the  plate  to  avoid 
accidental  blows  from  the  hammer.  The  holes  at  the  side 
are  for  screws  that  fasten  it  to  a  block,  with  a  central  hole 
through  which  the  pegs  fall  clear  as  they  are  knocked 
through  one  by  one  with  a  hammer. 

Allow  all  glued  joints  to  dry  before  boring  the  holes 
into  which  the  pegs  are  driven. 

A  cheap  circular  pattern  required  quickly  may  be  made 
of  plaster.  A  circular  pan  with  cover  (Fig.  66),  to  fix 
on  a  gas  fire  and  enclose  a  plumbers'  ladle,  may  be  taken 
as  an  example.  The  first  thing  required  is  a  flat  board 


Fig.  f>5.— Plate  for  Shaping  Wooden  Peg?. 

battened  on  the  underside  and  made  large  enough  to 
give  a  margin  of,  say,  about  4  in.  rovind  the  job  to  be 
strickled.  Next  procure  a  piece  of  square  stuff  and 
turn  it  down  in  the  lathe  at  each  end,  as  in  Fig.  67,  the 
length  between  the  shoulders  being  equal  to  the  depth 


48 


PRACTICAL   PATTERN  MAKING. 


inside  the  pattern  required.  Fix  this  in  the  centre  of 
the  board  by  means  of  the  short  peg,  driving  in  two  or 
three  nails  to  hold  it  firm. 

The  shape  of  the  pan  is  next  set  out  on  a  piece  of 
pine  about  1  in.  thick,  working  from  the  centre  line,  as 
shown  in  Fig.  68.  Set  out  the  thickness  of  the  metal 
required,  draw  a  parallel  line,  then  cut  away  to  the  inside 
line,  also  bore  a  hole  in  the  strickle  to  allow  it  to  revolve 
on  the  top  peg.  Everything  is  now  (ready  for  striking  up 
the  core.  The  space  between  the  strickle  and  the  upright 


Fig.  66.— Section  of  Circular  Pan,  with 
Cover. 


Fig.  67.— Axle  for 
Strickle. 


piece  forming  the  core  of  the  pan  may  be  filled  in  with 
scrap  wood,  room  being  left,  however,  for  a  layer  of 
plaster  of  Paris  to  finish. 

Superfine  plaster  should  be  used,  well  mixed,  and  all 
lumps  should  be  thrown  out.  In  laying  on  the  plaster, 
keep  working  the  strickle  round  on  its  centre,  the  result 
being  a  circular  core  of  the  shape  of  the  inside  of  the  pan. 
This  must  be  allowed  to  set  hard  and  afterwards  var- 
nished. While  this  is  drying,  cut  away  the  strickle  to  the 
second  line,  and  varnish  the  baseboard  where  the  strickle 
does  not  touch.  Oil  all  the  varnished  parts  and  again  lay 
on  the  plaster,  keeping  the  strickle  moving  round  all  the 
time,  the  result  being  the  outside  shape  of  the  pan.  Use 


CIRCULAR  PATTERNS'. 


the  plaster  fairly  thin  towards  the  finish  so  as  to  leave  the 
pattern  smooth.  Allow  it  to  set  hard,  and  varnish  it  in 
place.  When  quite  set,  the  shell  can  be  easily  removed 
from  the  core  and  the  required  pattern  is  complete.  This 
is  very  cheap  compared  with  making  a  similar  pattern  in 
wood.  The  cover  for  the  pan  is  worked  up  in  the  same 
manner,  core  first  and  pattern  afterwards. 


Fig.  69.— Edge 
of  Strickle. 


Fig.  68.— Strickling  Shell. 

Another  convenient  use  for  the  strickle  is  found  in 
striking  up  different  forms  of  mouldings  for  use  on  fancy 
patterns  both  straight  and  circular.  When  a  straight 
moulding  is  required,  nail  down  a  straight  edge  along 
which  to  run  the  strickle,  and  if  a  thin  shell  is  required, 
strike  up  the  core  first  as  in  the  circular  work,  adding,  of 
course,  the  varnish  and  oil.  A  strickle,  after  being  cut  to 
shape,  should  always  be  bevelled  at  the  back,  leaving  the 
front  edge  about  J  in.  thick,  as  shown  in  Fig.  69. 


50 


CHAPTEK  V. 

MAKING   COEE-BOXES. 

THE  sand  moulds  used  in  metal  casting  are  almost  always 
constructed  with  parts  made  of  dried  sand,  termed  cores, 
unless  the  shape  of  the  casting  is  a  simple  one.  To  form 
these  cores,  wooden  moulds  called  core-boxes  have  to  be 
made  by  the  pattern  maker. 

A  simple  cylindrical  core  is  one  which  is  constantly 
being  required,  and,  if  not  of  large  size,  is  always  made 
in  a  box  such  as  is  shown  in  Fig.  70.  Assuming  that  a 


Fig.  70. — Core-box  for  Plain  Circular  Core. 

core  3  in.  diameter  and  12  in.  long  is  wanted,  two  pieces 
of  wood,  each  measuring  a  little  over  12  in.  in  length,  about 
6  in.  or  7  in.  wide,  and  2  in.  thick,  are  dowelled  together 
face  to  face,  the  dowels  being  placed  towards  the  edges  of 
the  wood.  For  a  box  of  this  size,  dowels  would  be  put  in  two 
opposite  corners,  as  in  Fig.  71,  which  is  a  view  of  one  half 
of  the  box.  The  ends  are  then  squared  off,  and  the  length 
is  finished  to  the  required  size.  On  the  back  of  each  part, 
pieces  of  wood  termed  "  backing  "  are  glued  and  screwed, 
with  the  grain  running  at  right  angles  to  that  of  the  core- 


MAKING   COKE-BOXES. 


51 


box.  The  backing  is  generally  a  very  necessary  part  of 
the  core-box,  in  order  that  it  may  possess  sufficient 
strength  and  permanence  of  form. 

The  core  maker  raps  the  backing  with  a  mallet  to  loosen 
the  core  in  the  box,  and  to  save  it  as  much  as  pos- 
sible from  the  effects  of  the  blows,  the  backing  should  al- 
ways have  the  edges  well  chamfered  off,  and  the  holes 


Fig.  73.— Template  for  Work 
ing  Circular  Core-boxes. 


Fig.  71.— 
Half  of  Core- 
box,  showing 
Dowels. 


Fig.  7 2.— Core-box  for  Bend-pipe. 

through  which  the  screws  pass  deeply  countersunk.  A 
3-in.  circle  is  now  struck  on  one  end  of  the  box;  and 
from  each  point  of  that  diameter  of  the  circle  that  inter- 
sects the  joint  of  the  box,  gauge  lines  are  marked  on  one 
half  of  the  box.  Another  circle  is  struck  on  the  other 
end,  and  the  box  is  ready  to  be  worked  out.  This  is  done 
by  means  of  gouges  and  round-soled  planes. 

If  the  core-box  should  be  shaped  as  in  Fig.  72,  which 


PRACTICAL  PATTERN 


shows  a  core-box  for  a  bend-pipe,  planes  are  not  available, 
and  a  template  or  a  set-square  is  necessary  to  ensure  truth 
of  shape.  Fig.  73  shows  the  template,  which  is  used  by 
smearing  the  semicircular  edge  with  red  lead  and  oil,  and 
trying  in  the  box  from  time  to  time  as  the  cutting  out 
progresses.  If  a  set-square  is  used,  it  is  applied  as  in 
Fig.  74,  the  dotted  lines  showing  varying  positions  of  the 
square.  When  the  two  sides  rest  on  the  ed^jes  A  B,  the 
rectangular  corner  of  the  set-square  c  will  always  occupy 
a  point  in  the  circle  which  has  A  B  for  a  diameter.  It  is 
best  to  make  a  special  set-square  for  this  purpose,  about 
i  in.  or  Tn(.r  in.  thick,  with  a  little  steel  plate  inserted  in  a 
saw-cut  (see  Fig.  75)  and  riveted  through.  The  thickne:  :•>  of 
the  square  will  then  prevent  the  edges  of  the  box  being 


Fig.  74.— Working  Out  Circular 
Core-box  with  Set-square. 


Fig.  7o.— Fixing  Steel  Plate 
in  Corner  of  Set-square. 


damaged,  and  the  steel  plate  will  resist  the  wearing  action 
at  the  angle,  which  would  otherwise  soon  render  the  square 
useless  for  this  purpose.  Fig.  75  is  a  sketch  of  the  corner 
of  the  square. 

In  making  a  core  in  the  box  shown  in  Fig.  70,  the  two 
parts  would  be  clamped  together,  the  box  placed  upright 
and  sand  rammed  into  the  cylindrical  space.  When  it  is 
either  impossible  or  awkward  to  ram  the  core  from  the 
end,  as  in  Fig.  72,  the  ends  are  stopped  by  screwing  on 
pieces  of  backing  stuff,  as  shown.  The  two  halves  of  the 
core  are  then  rammed  separately,  and  the  halves  of  the 
box  are  brought  together  after  a  wash  made  of  clay  and 
water  has  been  smeared  on  to  fasten  together  the  halves  of 
the  core. 

When  an  internal  flange  is  required  in  a  straight  box 
of  any  considerable  length,  such  as  A  (Fig.  76),  it  is  usually 


MAKING   CORE-BOXES.  53 

best  to  cut  through  to  the  greater  diameter,  and  then  let 
in  the  flange  (which  is  turned  in  halves)  as  shown.  If, 
however,  a  large  number  of  them  were  required  somewhat 
close  together,  it  would  be  best  to  cut  through  to  the 


Fig.  76.— Intemal  Flange  Fitted  into  Core-box. 

smaller  diameter,  and  cut  out  to  the  larger  diameter  with 
gouges. 

Cores  of  the  shape  of  Fig.  77  are  called  "chamber 
cores,"  and  are  frequently  required.  If  the  chambered 
part — namely,  that  having  the  greater  diameter — is  long, 
whilst  the  remaining  part  is  short,  a  good  way  of  making 
the  box  is  to  cut  through  to  the  large  diameter,  and  then, 


Fi?.  77. — Chamber  Core. 

cutting  away  the  ends,  make  up  with  blocks  placed  trans- 
versely, and  cut  these  through  to  the  small  diameter. 
This  is  shown  in  Fig.  78.  If  the  box  is  required  for 
making  a  few  cores  only,  it  will  then  be  sufficiently  strong 
without  backing.  If  the  part  having  the  smaller  diameter 
be  very  short,  a  plain  piece  may  be  screwed  on  to  the  end 
and  worked  through,  as  shown  in  Fig.  79. 


54  PRACTICAL  PATTERN  MAKING. 

Cores  which  are  rectangular  solids,  or  approximate  to 
being  so,  are  of  a  shape  which  is  very  much  required.    Sup- 


Fig:.  78. — Core-box  for  Chamber  Core. 


pose  a  small  core,  as  Fig.  80,  to  be  required,  then  the  box 
is  made  as  shown  in  Fig.  81,  with  one  diagonal  along  the 
line  of  the  joint.  This  ensures  the  box  coming  freely 
away  from  the  sand  after  ramming.  In  making  the  core, 
the  two  parts  of  the  box  are  held  together,  placed  on  a 
flat  board,  and  scraped  off  level  after  ramming. 


Fig.  79.— Core-box  with  End  of  Small  Diameter. 

Such  a  method  of  construction  as  that  shown  in  Fig. 
8 1  is  applicable  only  to  core-boxes  which  are  of  the  smallest 


MAKING  CORE-BOXES.  55 

size.  For  larger  cores  the  construction  shown  in  Fig.  82 
is  almost  invariably  used.  The  ends  are  housed  into  the 
sides,  and,  when  the  core  is  rammed,  some  of  the  screws 
are  slackened  so  that  it  may  be  more  easily  removed  from 
the  box  as  at  A.  For  large  boxes,  screwed  pins  and  bow 
nuts  are  used  instead  of  ordinary  wood  screws ;  this  is 
shown  at  the  corner  B.  Bosses,  ribs,  or  other  projections 
with  axes  at  right  angles  to  either  of  the  sides  or  ends 
may  be  fixed  on,  and  when  the  fastenings  of  the  box  are 
removed  the  side  or  end  may  be  drawn  away  without  dis- 
turbing the  sand.  If  bosses  are  required  on  the  bottom 


Fig.  Sl.     ^U/"  ^l^        rig.  80. 

Figs.  80  and  81.— Rectangular  Core  and  Core-box. 

of  the  core,  the  box  is  dowelled  on  to  a  bottom  board  upon 
which  the  boss  or  rib  may  be  fastened.  A  boss  may  be 
formed  on  the  top  of  the  core  by  dowelling  across  it  a 
narrow  bridge-piece,  upon  the  underside  of  which  the  boss 
is  fixed.  A  boss  inclined  at  an  angle  to  one  of  the  sides 
may  be  formed  by  making  the  boss  loose,  and  withdrawing 
it  after  the  sides  are  taken  away;  or  a  plug  having  a 
shoulder  to  ensure  it  being  properly  placed  is  passed 
through  the  box,  and  the  boss  formed  upon  the  end  inside 
the  box.  This  plug  is  withdrawn  from  the  core  before  the 
sides  of  the  box  are  removed.  The  centre  line  of  the  hole 
through  which  it  passes  is,  of  course,  at  the  same  angle 
as  the  boss. 


53 


PRACTICAL  PATTERN  MAKING. 


Large  round  cores  are  generally  formed  without  using  a 
box  at  all  but  in  special  cases  a  box  is  required,  and  then 
it  is  built  up  as  in  Fig.  83.  A  number  of  lagging  pieces  are 
fitted  into  transverse  pieces  A,  and  end  pieces  B  are  fitted 
on  after  the  shape  of  the  box  is  worked  out  as  at  c.  In 
most  cases  a  half  box  is  sufficient,  the  two  half  cores,  after 
being  made,  being  fastened  together. 

Fig.   84  is  another  case  in  which  a  half  box  may  bo 


Fig.  82. — Built-up  Box  for  Large  Rectangular  Core. 

used,  but  for  Fig.  85  a  whole  box  would  have  to  be  made, 
for  the  two  halves  of  the  core  would  overlap  each  other  if 
placed  face  to  face.  Fig.  86  shows  the  shape  of  a  core 
which  can  be  made  with  a  half  box  if  provision  is  made 
for  placing  the  branch  on  one  half  to  the  full  lines,  and  on 
the  other  to  the  dotted  lines.  This  is  done  by  having  two 
branch  pieces  cut  out,  and  stopping  one  off  when  one  half 
core  is  made,  and  the  other  part  when  the  other  half  is 
made. 

In  moulding  flywheels,  spur  wheels,  and  large  pulleys, 


MAKING  CORE-BOXES. 


57 


core-boxes  such  as  Fig.  87  are  in  general  use.  If  the  wheel 
has  six  arms,  a  segmental  box  embracing  one-sixth  of  a 
circle  is  built  up,  and  in  this  a  pattern  of  one-sixth  of  the 
wheel  is  fitted.  The  sides  are  made  to  come  apart  and 


Fig.  83.— Half  Box  for  Large  Circular  Core. 

withdraw  separately  from  the  core,  leaving  the  arm  in  the 
middle  of  the  core  to  be  withdrawn  afterwards.  If  for  a 
flywheel,  the  face  is  made  by  means  independent  of  the 
core-box.  If  for  a  spur  wheel,  another  segmental  box  is 


Fi 


Fig.  85. 
Figs.  84  and  85.— Symmetrical  and  Unsymmetrical  Cores. 

made  for  forming  the  teeth,  and  the  cores  made  in  it  aro 
laid  in  a  circle  in  the  mould.  Thus  a  nearly  complete 
mould  is  formed  by  laying  the  cores  on  a  flat  bed  of  sand. 


58  PRACTICAL  PATTERN  MAKING. 

The  top  is  covered  up  either  by  making  a  ring  of  flat  seg- 
mental  cores,  or  by  covering  with  a  box  of  sand  rammed  up 
and  scraped  off  to  a  flat  surface. 


Fig.  86.— Core  for  Bend-pipe  Fig.  87.— Core-box  for  Making 

with  Branch.  Flywheel. 

A  complete  pattern  may,  of  course,  be  used  instead  of 
core-boxes,  and  in  the  case  of  small  castings  it  is  some- 
times better  to  do  so,  but  core-boxes  are  almost  always 
used  for  large  castings  for  the  sake  of  reducing  the  cost  of 
pattern  making. 


CHAPTER  VI. 

CORING  HOLES  IN  CASTINGS. 

IN  very  many  cases  the  best  method  of  coring  a  hole  is 
obvious  and  simple  enough ;  but  it  is  otherwise  in  a  large 
number  of  instances.  It  is  proposed  to  give  in  this  chapter 
a  few  examples  of  this  class  of  work. 

Take  first  one  of  the  very  simplest  cases  that  can  occur, 
a  plain  cylinder  cover  (shown  in  Figs  88  and  89).  To  core 
the  centre  hole  A  for  the  stuffing-box  and  piston-rod,  a  print 


Fig.  89. 


Figs.  88  and  89.— Casting  of  Cylinder  Cover. 

is  put  on  the  pattern  on  the  side  which  goes  downwards 
in  the  mould.  This  is  shown  on  the  pattern  at  A  (Fig.  90), 
where  the  pattern  is  illustrated  in  the  position  in  which 
it  is  withdrawn  from  the  mould.  Since  the  hole  is 
shouldered,  that  is,  not  parallel  throughout,  a  core-box 
must  be  made.  This  is  illustrated  in  Figs.  91  and  92.  The 
core  made  from  this  is  dropped  into  the  print  impression 
A  in  the  mould,  and  is  thus  centred  and  retained  in  its 


60  PRACTICAL  PATTERN  MAKING. 

correct  position.  The  mould,  with  its  core  in  place,  is 
shown  in  section  in  Fig.  93. 

This  is  a  very  common  illustration  of  the  simplest  kind 
of  coring.  Almost  all  holes  which  pass  vertically  through 
castings  are  formed  by  the  insertion  of  cores  thus  set 
in  print  impressions  in  the  lower  portion  of  the  mould. 
There  are  a  few  special  exceptions,  as  in  the  case  of  work 
for  which  the  cores  are  so  large  that  they  are  set  in  place 
by  measurement  alone,  since  they  do  not  need  assistance 
from  the  impressions  of  prints. 

All  prints  which  are  used  for  vertical  cores  are  tapered, 
or  coned  smaller  in  a  direction  away  from  the  pattern  face. 
This  is  shown  in  Fig.  90.  It  is  done  to  prevent  the  print 
from  tearing  up  the  sand,  which  a  parallel  print  would 
almost  certainly  do  on  withdrawal.  The  reason  why  a 
larger  amount  of  taper  is  given  to  a  print  than  to  its 


Fig.  9i '.—  Cylinder  Cover  Pattern. 

pattern  is  that  a  moulder  always  desires  the  maximum 
taper  which  is  permissible  in  any  case.  He  cannot  have 
just  what  he  likes  in  a  pattern,  but  he  can  in  prints,  and 
so  he  gets  it.  It  is  better,  too,  that  a  core  print  should 
have  plenty  of  taper  because  when  a  print  tears  up  the 
mould,  the  latter  has  to  be  made  good  again ;  and  if 
badly  broken,  it  probably  would  not  be  mended  quite 
accurately,  and  then  the  core  would  be  set  out  of  truth  and 
the  hole  in  the  casting  be  correspondingly  out  of  truth.  It 
may  be  noted,  further,  that  while  the  print  is  tapered  there 
is  no  taper  in  the  core-box  (Figs.  91  and  92)  to  correspond  ; 
consequently,  taper  has  to  be  filed  or  rubbed  on  the  core 
to  make  it  enter  and  fit  the  print  impression  exactly. 

When  a  few  castings  only  are  wanted,  it  is  not  usual  to 
put  the  print  taper  in  the  core-box  ;  but  if  many  (say 
twenty  and  upwards)  are  required  the  taper  should  be 
formed  in  the  box  to  correspond  with  that  given  to  the 
print.  It  saves  the  moulder's  time,  and  reduces  the 


CORING  HOLES  IN  CASTINGS.        61 

risk  of  the  cores  being  set  out  of  the  vertical,  due  to  more 
being  filed  off  one  portion  of  the  sides  of  the  core  than  off 
others. 

There  is  yet  another  point  of  importance.  One  print 
only  is  shown  on  this  pattern  (that  on  the  bottom),  and 
it  is  sufficient  in  the  example  given.  But  suppose  the 
length,  or  height,  of  the  core  were  double  or  treble  what 
it  is,  then  one  print  alone  could  not  be  trusted  to  hold 
safely  the  core  upright.  In  such  a  case  a  second,  or  steady, 
print  is  put  on  the  top  face  to  make  a  hole  for  the  top  end 
of  the  core.  This  is  shown  dotted  at  B  (Fig.  90). 

Many  cases  occur  in  which  top  prints  are  absolutely 
necessary ;  but,  obviously,  lengths  and  diameters  are  re- 


Fig.  91. 


Fig.  92. 


Fiyrs.  91  and  92. — Core-box 
for  Cylinder  Cover. 


Fig.  93.— Mould  for  Cylinder  Cover. 


Intive.  So  that  if  a  core  were  4  in.  diameter  and  12  in. 
high,  it  could  be  set  safely  in  a  bottom  print  alone ;  but  if 
it  were  1  in.  in  diameter  and  12  in.  high,  a  top  print  would 
be  required.  Also,  a  long  vertical  core  may  be  held  by 
a  bottom  print  alone  if  there  is  a  good  chance  of  centering 
it  by  measurement  right  up  to  the  top  ;  otherwise,  a  re- 
latively short  core  may  require  a  top  print.  For  example, 
in  Fig.  93  measurement  can  be  taken  in  the  mould  from 
the  edge  of  the  core  to  the  edge  of  the  mould,  the  radius 
A  A  being  easily  taken.  Then  the  question  of  the  securing 
of  the  core  in  the  top  simply  means  the  thrusting  of  the 
core  well  into  its  print  impression,  and  the  application 
of  the  pressure  of  the  cope  on  the  top  of  the  core.  Many 
cases,  however,  arise  in  which  a  large  portion  of  the  mould 
comes  up  into  the  top  and  the  core  has  to  pass  up  into  it, 
and  measurement  cannot  be  taken  at  the  top.  Then 


G2  PRACTICAL  PATTERN  MAKING. 

a  top  print  is  desirable  to  guide  the  core  correctly,  be- 
cause the  moulder  cannot  see  and  measure  it.  In  some 
later  examples  attention  will  again  be  drawn  to  this  im- 
portant point. 

Cases  arise  in  which  top  prints  cannot  conveniently  be 
used.  Then  the  difficulty  is  often  got  over  by  making  the 
bottom  print  double,  or  even  treble,  the  usual  length,  so 
that  it  shall  form  an  efficient  stay,  as  well  as  a  guide  to  the 
core. 

The  lengths  of  these  prints  and  the  amount  of  taper  to 
be  given  to  them  vary  within  wide  limits.  For  bottom 
prints  up  to  2i  in.  or  3  in.  diameter,  the  length  is  usually 
made  about  equal  to  the  diameter;  over  these  diameters 
the  length  diminishes.  But,  after  all,  the  length  depends 
in  the  main  on  the  length  of  core  which  the  print  is  re- 
quired to  steady  ;  so  that  for  coring  through  thin  plates 
of  metal,  prints  of  2  in.  diameter  need  not  be  more  than 
i  in.  or  |  in.  long,  or  thick.  For  coring  through  a  con- 
siderable depth  without  top  prints,  a  2  in.  print  would 
sometimes  be  made  3  in.  or  4  in.  long.  For  coring  holes  at 
a  bevel,  prints  are  made  longer  than  for  similar  cores  set 
vertically. 

As  regards  taper,  an  average  print  will  be  tapered 
about  ^  in.  in  its  length — few  less,  the  larger  ones  more. 
Both  length  and  taper  are  therefore  matters  to  be  decided 
upon  according  to  the  requirements  of  each  individual  job. 

Another  matter,  very  obvious  apparently,  relates  to  the 
length  to  which  core-boxes  must  he  made  or  cores  cut  off. 
This  length  must  always  include  the  length  of  core  re- 
quired in  the  casting,  plus  the  length  of  print  on  the 
pattern.  That  is  obvious  on  comparing  Figs.  88  and  93. 

When  holes  have  to  be  cored  in  horizontal  positions  in 
the  mould,  either  two  prints  or  one  may  be  used,  but  taper 
is  not  required  in  the  portion  of  the  print  that  forms  the 
impression  for  the  core.  In  the  case  of  what  are  called 
"pocket"  or  "drop"  prints,  the  portions  above  the  part 
which  corresponds  with  the  core  are  tapered.  Two  prints 
are  employed  when  the  mould  is  wide,  and  only  one  when 
it  is  narrow. 

Taking  a  familiar  object,  Figs.  94  and  95  illustrate  a 
plain  steam  cylinder  casting  in  longitudinal  and  in  trans- 
verse sections.  The  central  bore  A  has  to  be  cored  with  a 


CORING  BOLKS 


CASTINGS. 


63 


horizontal  core  laid  in  two  parallel  print  impressions. 
The  passages  c  c  B  have. to  be  formed  with  cores  laid  in 
bottom  tapered  print  impressions ;  B  will  be  supported  at 
the  other  end  c  (Fig.  95)  in  a  parallel  print  impression  ; 
c  c  are  supported  at  one  end  only  by  prints.  At  the 
opposite  ends  they  abut  against  the  main  core  A.  In  some 
exceptional  cases  core  print  impressions  for  c  are  cut  in  A, 
so  fulfilling  the  purpose  of  top  prints ;  but  jn  general 
work  it  is  more  convenient  to  dispense  with  their 
assistance. 

Figs.  96  and  97  illustrate  the  pattern  of  this  cylinder 
in  the  position  in  which  it  would  lie  in  the  mould.     The 


c   B    c 

Fi<?.  94.  Fig.  95. 

Figs.  91  and  95.— Casting  of  Engine  Cylinder. 

prints  are  lettered  similarly  to  the  cored  portions  in  Figs. 
94  and  95  for  convenience  of  reference  and  identification. 
Fig.  98  shows  a  longitudinal  section  and  Fig.  99  a  trans- 
verse section  of  the  mould  cored  up — that  is,  with  the  cores 
inserted  in  their  places. 

The  reason  why  taper  is  not  necessary  in  prints  for 
horizontal  cores  is  now  clear.  Still,  it  is  not  so  obvious 
to  those  who  have  not  had  opportunities  of  considering 
pattern-making  as  it  is  seen  from  the  standpoint  of 
the  moulder.  The  only  reason  why  prints  are  made  taper- 
ing is  to  facilitate  their  withdrawal  from  the  mould. 
As,  therefore,  these  horizontal  prints  do  not  withdraw 
in  the  direction  of  their  longitudinal  axis,  taper  in  that 
direction  would  be  worse  than  useless,  because  that  would 


61  PRACTICAL  PATTERN  MAKING. 

involve  filing  the  core  to  correspond.  The  half  pattern 
bodies  are  withdrawn  in  the  direction  of  the  arrows  seen 
in  the  end  view,  Fig.  97,  and  the  semicircular  forms  of  the 
prints  are  all  in  favour  of  withdrawal.  To  prevent  the 


Fig.  96.—  Engine  Cylinder  Pattern. 


print  ends  c  c  B  from  tearing  up  the  sand,  they  are 
properly  tapered  and  the  ends  are  slightly  rounded,  as 
shown  in  the  elevation  of  the  pattern  (Fig.  96).  Or  some- 
times the  moulder  cuts  the  sand  clean  away  from  the  ends. 
In  Figs.  96  to  99  it  will  be  noted  that  the  amount  of 
taper  on  the  prints  c  c  B  is  rather  more  than  usual.  The 


Fig.  97.— Engine  Cylinder  Pattern. 

reason  is  because  the  quantity  of  sand  between  adjacent 
prints  is  so  slight  that  a  good  deal  of  taper  is  necessary 
to  prevent  the  pulling  up  of  the  sand.  And  not 
only  so,  but  the  moulder  frequently  inserts  slips  of  hoop 


CORING  HOLES  IN  CASTINGS.        65 

iron  close  alongside  the  prints,  so  flanking  and  reinforcing 
the  weak  sand  during  the  withdrawal  of  the  prints  and  the 
insertion  and  securing  of  the  cores.  And  further,  many 


^v-yffitg^.^f^^ 


Fig.  98.— Mould  for  Engine  Cylinder. 

cylinders  are  cast,  not  with  three  separate  passage  cores 
entering  into  separate  print  impressions,  but  with  three 
cores  rammed  in  one  and  entering  into  a  block  print  im- 
pression common  to  all  three.  This  is  done  to  avoid  the 


Fig.  99.— Mould  for  Engine  Cylinder. 

troublesome  separate  prints  and  cores  and  fixing  of  the 
latter. 

The  reason   why  print  impressions   are   not  necessary 


Pit  AC  TIG  AL  PATTEUX  MAKING. 


to  secure  the  top  ends  of  the  passage  cores  A  A  is  apparent 
from  Figs.  98  and  99.  The  cores  are  supported  by  one 
or  more  chaplet  nails  D  D  (Fig.  98),  upon  which  they  -rest, 
and  E  E  (Fig.  99),  which  prevent  side  movement,  while  they 
are  prevented  from  rising  by  the  pressure  downwards  of 


Figs.  100  to  102.— Square  Print, 

the  main  core  A.  The  nails  E  E  are  not  required  in  small 
work,  but  only  in  the  case  of  cores  of  large  dimensions. 

In  Figs.  96  to  99,  the  centre  planes  F  F  of  the  core  A 
and  its  prints  coincide  exactly  with  the  joints  of  the  pattern 
and  of  the  mould,  and  these  are  typical  of  an  immense 
number  of  cases  which  arise.  But  in  an  equal  number  the 
central  planes  and  pattern  mould  joints  are  not  coincident, 
and  then  prints  of  other  forms  are  used. 

The  sides  of  the  main  prints  for  the  cylinder  bore 
facilitate  delivery  and  withdrawal,  because  they  are 


Fig.  103.  Fig.  104. 

Figs.  103  and  104.— Square  Print  Jointed  Diagonally. 

semicircular.  But  it  happens  frequently  that  core  prints 
are  of  such  a  shape  that  they  do  not  deliver  freely,  and 
then  they  are  made  to  taper  sideways — never,  of  course, 
lengthwise. 

If  a  square   print  A  (Figs.    100  and   101)  were   jointed 


COEING  HOLES  IX  CASTINGS. 


f;7 


diameter-wise  as  c  c  (see  also  Fig.  102),  the  mould  would 
be  vertical,  and  would  probably  be  torn  up  during 
the  lifting  if  the  cope  were  lifted  off  the  pattern. 
Or  the  lowering  of  the  cope  down  by  the  edges  of  the 
core  would  probably  crush  the  sand  or  the  core.  Then 
two  courses  are  usually  open.  One  is  not  to  joint  the 
print,  but  to  make  the  mould  joint  come  along  the  top 
face  B  B,  and  to  taper  the  print  slightly  downwards. 
Then  the  print  draws  wholly  in  the  direction  of  the  arrows, 
and  there  is  no  risk  of  the  sand  in  the  cope  or  the  core 
becoming  crushed.  Another  way  often  practised  is  to  turn 
the  pattern  joint  round  45°,  and  with  it  the  print,  bringing 


Fig.  106. 
Figs.  105  and  106.— Steam  Chest  Casting. 

the  joint  diagonal  wise,  as  shown  in  Figs.  103  and  104 ; 
then  there  is  not  the  least  difficulty  either  in  moulding  or 
in  coring  up.  If,  however,  the  print  must  be  jointed,  as  at 
c  c,  in  Figs.  100  and  101,  then  a  common  practice  is  to 
make  the  top  half  wider  than  the  bottom  half,  and  to  taper 
it  more  freely.  The  effect  of  this  is  to  prevent  tearing  of 
the  sand,  and  also  crushing  during  coring  up.  The  core 
fits  tightly  in  the  bottom  half,  and  easily  in  the  top ;  but 
it  cannot  shift,  because  secured  in  the  bottom,  and  the 
only  disadvantage  is  the  presence  of  a  slight  fin  between 
the  sides  of  the  core  and  those  of  the  top  print  impression 
but  this  fin  is  easily  chipped  off. 

The    forms    and    purposes    of    prints    for    vertical    and 


68 


PRACTICAL  PATTERN  MAKING. 


horizontal  cores  in  which  the  central  plane  of  the  prints 
generally  coincides  with  the  main  joints  of  the  pattern,  and 
the  mould  having  been  considered,  the  case  of  prints  for 
horizontal  cores,  in  which  the  plane  of  the  print  and  of  the 
pattern  do  not  agree  will  now  be  taken. 

In  some  instances  a  plain  round  parallel  print  is  made 
for  use.  Two  principal  cases  occur— one  in  which  the 
moulder  can  make  a  sloping  joint  from  the  main  joint 
to  the  centre  of  the  print  and  core  ;  the  other,  that  in 
which  the  print  can  be  drawn  back  into  the  mould,  and 
the  core  be  inserted  from  the  interior  of  the  mould.  Figs. 


Fig.  108.  Fig.  10!). 

Figs.  107  to  109.— Steam-chest  Pattern. 

105  to  110  illustrate  a  job  of  the  first  kind.     Figs.  105  and 

106  represent  a  cylinder  steam  chest,  in  which  it  is  desired 
to  core  the  stuffing-box  and  valve-rod  hole  A.     The  pattern 
must  mould  flatwise,  and  the  moulder's  main  joint  has  to 
be  made  along  the  plane  c  c  (Fig.  106),  while  the  centre 
of  the  stuffing-box  is  in  the  plane  B  B.     Figs.  107  and  108 
show  the  pattern  provided  with  a  long  round  parallel  print 
A  for  the  core.     What  is  termed  a  pocket  print  might  be 
used,  but  it  is  not  so  suitable  for  the  job  as  the  round 
print  shown.     The  use  of  a  (round  print  entails  upon  the 
moulder    a    little    down-jointing.       This    is    objectionable 
in  deep  faces,  but  not  so  in  the  case  of  a  shallow  face, 
as   in   this   instance.     The   slope   of  the   down-jointing  is 


CORING  HOLES  IN  CASTINGS.  ei) 

indicated  by  the  dotted  lines  on  the  ends  of  the  pattern 
in  Fig.  109,  coming,  it  will  be  noted,  to  the  centre  of  the 
print  A  and  the  plane  B  B  in  Fig.  106.  The  mould  is 
shown  in  section  in  Fig.  110.  The  print  is  of  sufficient 
length  to  counterbalance  the  weight  of  the  core  A,  thus 
preventing  risk  of  the  core  being  moved  out  of  truth. 


Fig.  110.— Mould  for  Steam-chest. 

If  the  round  core  were  not  made  so  long,  it  would  be 
necessary  to  support  the  core  at  the  inner  end  on  another 
print  impression  (shown  dotted  at  c),  which  would  have  to 
be  that  of  a  pocket  print.  The  shallow  print  for  the 
steam  inlet  core  B  affords  an  illustration  of  the  remark 
previously  made  to  the  effect  that  prints  used  for  coring 
through  thin  plates  of  metal  need  be  very  thin  only. 


Fig.  112. 


Figs.  Ill  and  112.— Casting  of  Hand  Capstan  Boss. 

Thus,  as  there  is  not  the  slightest  risk  of  the  core  B 
toppling  over,  the  print  in  thickness  or  length  is  not 
above  one-fourth  its  diameter.  But  the  print  for  the  core  A, 
on  the  contrary,  which  is  liable  to  fall,  is  more  than  twice 
its  diameter  in  length,  being  longer  than  that  portion  of 
the  core  which  hangs  over  into  the  mould. 


70 


PRACTICAL  PATTERN  MAKING. 


Figs.  Ill  to  116  illustrate  the  second  case  named— that 
in  which  round  prints  can  be  drawn  into  the  mould  without 
down-jointing,  and  the  cores  inserted  from  the  interior 
of  the  mould.  Figs.  Ill  and  112  show  a  casting  of  a  small 
hand  capstan  boss,  used  in  some  machines.  It  has  a 
central-shaft  hole,  and  six  holes  cast  for  the  turning  bar. 
If  round  prints  were  fastened  firmly  to  the  pattern,  the 
moulder  would  have  to  make  six  sloping  down-joints,  which 


Fig.  113. 


Fijr.  115. 


Fig.  114. 


Figs.  113  and  114.— Hand  Capstan 
Boss  Pattern. 


Fig.  116. 

Figs.  115  and  116.— Mould  for 
Hand  Capstan  Boss. 


he  would  prefer  not  to  do.  To  put  on  six  pocket  prints 
would  prevent"  this,  but  it  would  give  him  equal  trouble 
in  stopping  over  six  cores.  But  if  six  round  prints  are 
attached  loosely  with  skewers,  as  in  Figs.  113  and  114, 
which  illustrate  the  pattern,  these  prints  wrill  be  all  left 
behind  in  the  mould  after  the  withdrawal  of  the  main 
portions  of  the  pattern,  and  then  they  can  be  drawn  back 
singly  into  the  mould,  each  in  the  direction  of  its  longi- 
tudinal axis.  This  method  of  withdrawal  is  practicable 
only  when  there  is  sufficient  clear  space  in  the  mould. 


CORING  HOLES  IN  CASTINGS. 


71 


These  prints  do  not  require  taper,  because  as  the 
moulder  withdraws  each  singly,  he  can  by  gentle  rapping 
and  shaking  loosen  the  front  or  inner  ends  of  the  prints 
sufficiently  to  ensure  clean  withdrawal.  The  cores  are 
more  likely  to  be  inserted  truly  also  than  if  they  had  to 
be  filed  to  fit  tapered  prints.  If  a  special  core  box  were 
made,  then  prints  and  cores  could  be  tapered  with  ad- 
vantage. Figs.  115  and  116  show  the  mould  with  the  cores 
inserted.  They  are  all  readily  put  into  their  print  im- 
pressions from  the  interior  of  the  mould,  previous  to  the 
insertion  of  the  central  core.  The  joint  between  the  top 
and  bottom  parts  of  the  mould  is  in  the  plane  A  A. 


o 


o 


o 


o 


Fig.  118. 
Figs.  117  and  118.— Bracket  Casting. 

Many  jobs  occur  in  which  the  use  of  round  prints  for 
coring  horizontal  holes  is  not  practicable,  and  in  which 
the  amount  of  down-jointing  would  be  too  great,  and  in 
which  there  is  not  sufficient  open  space  in  the  mould  to 
withdraw  the  prints  into.  In  such  cases  the  pocket  or  drop 
print  offers  the  only  alternative.  This  will  now  be  illus- 
trated and  described. 

The  bracket  in  Figs.  117  and  118,  in  which  holes  are 
cored  in  the  foot,  is  selected  to  illustrate  the  typical  pocket 
prints.  The  bracket  pattern  is  not  moulded  as  the  casting 
stands  when  bolted  down  by  the  foot,  but  as  in  Figs.  119 
and  120.  Neither  down- jointing  nor  drawing-in  of  prints 
is  practicable,  for  this  reason  the  pocket  prints,  shown  in 
Figs.  119  and  120  or  Fig.  121  are  employed.  Figs.  119  and 


72 


PRACTICAL  PATTERN  MAKING. 


120  illustrate  one  method,  in  which  distinct  prints  are  used 
for  each  core ;  Fig.  121  illustrates  a  method  by  which  one 
print  does  duty  for  two  cores.  The  latter  requires  a  special 
core-box,  the  former  needs  no  core-box.  Fig.  122  illus- 


trates the  mould  cored  up  for  Fig.  119 ;  Fig.  123  the  same 
cored  up  for  Fig.  121.  Everything  will  be  clear  on  a 
comparison  of  the  figures. 

In  Figs.  119  and  120  the  prints  A,  for  the  holes  which 


CORING  HOLES  IN  CASTINGS. 


73 


come  uppermost,  are  fastened  on  the  outer  faces  of  the 
prints  B,  which  core  out  the  lower  holes.  The  first 
are  also  thicker  than  the  second.  In  Fig.  121  there  is 
no  indication  in  the  pattern  of  any  provision  for  coring 


Fig.  121.— Foot  of  Bracket  Pattern. 


out  the  upper  holes,  one  print,  A,  only  being  used.  In 
all  cases  in  which  a  core-box  is  not  provided  prints 
must  be  put  on  as  shown  in  Figs.  119  and  120— namely,  a 
distinct  print  opposite  each  hole.  Then  the  moulder  in- 


HHB 


M 


Fig.  122.— Section  through  Cored  Mould. 

serts  common  round  cores  in  tli3  print  impressions  and 
stops  them  over  with  sand,  as  ia  Fig.  122.  In  all  cases  in 
which  a  single  print  only  is  used  for  two  cores,  as  in  Fig. 
121,  a  core-box  like  Figs.  124  and  125  must  be  made  and 


PRACTICAL  PATTERN  MAKING. 


sent  with  the  pattern.  The  latter  method  ensures  a  more 
accurate  location  of  holes  in  the  casting  than  the  former, 
for  the  following  reasons : — 

The  prints  in  Figs.  119  and  120  should  be  thick  enough 
to  counterbalance  their  cores,  and  the  reason  why  the 
top  print  A  is  made  so  much  thicker  than  the  lower  one 
B  is  because  its  core  has  to  bridge  a  wider  space  than 
the  lower  one.  Then  it  is  not  easy  to  ensure  accurate 
setting  of  the  cores,  because  they  have  to  be  lowered 
deeply  into  the  mould  on  the  bent  end  of  a  cleaner,  often 
by  the  reflected  light  of  a  lamp.  In  stopping-over,  also, 
the  cores  are  liable  to  shift.  But  made  as  in  Fig.  121, 
with  a  core  rammed  in  the  box  (Figs.  124  and  125),  the  core 


Fig.  123.— Section  through 
Portion  of  Cored  Mould. 


Fig.  124. 


Fig.  125. 

Figs.  124  and  125. — Core-box  for 
Foot  of  Bracket. 


is  dropped  into  its  place,  as  shown  in  Fig.  123,  at  once, 
without  risk  of  shifting,  and  without  any  stopping-over 
being  necessary.  When  the  core-box  is  made  truly,  the 
holes  in  the  casting,  or  in  twenty  castings,  made  from  the 
same  pattern  and  box  are  bound  to  be  precisely  alike. 
Such  perfect  uniformity  could  not  possibly  be  ensured  by 
the  method  of  Figs.  119  and  120 ;  so  that  to  secure  the  best 
results  in  all  cases  it  is  better  to  adopt  the  method  illus- 
trated in  Fig.  121  and  Figs.  124  and  125. 

The  stopping-over  of  the  cores  is  effected  by  means  of 
a  board  A  (Figs.  126  and  127),  cut  to  a  semicircular  shape 
at  the  bottom,  to  fit  over  and  rest  upon  the  core.  The  face 
of  the  board  is  held  against  the  face  c  of  the  mould,  and 
the  space  B  left  by  the  print  is  then  filled  up  and  rammed 
with  sand.  This  completely  fills  up  the  print  impression, 


GORING  HOLES  IN  CASTINGS. 


and  it  is  kept  from  falling  into  the  mould  by  the  face  of  the 
board  A,  which  also  maintains  the  filled-in  sand  level  with 
the  vertical  mould  face  of  the  foot.  When  the  bottom  core 
is  thus  stopped  over,  the  top  one,  which  goes  in  the  print 
impression,  is  similarly  treated.  In  Fig.  122  the  cores  DE 
are  seen  stopped  over  with  the  sand  which  fills  up  the 
print  impressions  A  and  B.  Obviously,  the  method  shown 
in  Figs.  121  and  123  and  Figs.  124  and  125  is  preferable  in 
all  respects. 

Allusion  has  been  made  to  cases  in  which  a  rather  short 
core  may  require  the  assistance  of  a  top  steady  print, 
because  of  the  difficulty  of  centring  it  otherwise.  Figs. 


:-••-  Fig.  127. 

Fig.  126. 
Figs.  126  and  127.— Stopping-over  Board  for  Cores. 

119  and  120  and  Fig.  122  afford  a  case  in  point.  The 
pattern  and  mould  are  both  jointed  along  the  plane  c  c, 
so  that  the  upper  part  D  of  the  boss  through  which  the 
core  E  passes  is  in  the  top  part  of  the  mould,  and  the  core 
E  cannot  therefore  be  checked  for  truth  any  higher  than 
the  moulder's  joint  c  c.  Hence  the  advantage  of  a  top 
print  in  this  case — a  print  which  could  be  dispensed  with  if 
the  joint  of  the  mould  came  along  the  top  face  of  the  upper 
part  d  of  the  boss. 

When  a  bracket  is  of  the  shape  shown  in  Figs.  128  and 
129,  there  are  two  ways  of  putting  on  pocket  prints.  Here 
there  are  four  bolt  holes,  and  the  shape  of  the  casting 
is  such  that  the  top  face  of  the  web — compare  with  the 
pattern,  Fig.  130 — coincides  with  the  moulder's  joint 


76 


PRACTICAL  PATTERN  MAKING. 


between  top  and  bottom  flasks,  the  joint  of  the  pattern  B  B 
(Figs.  130  and  131)  being  also  on  the  same  plane.  In 
such  a  case  there  are  three  different  ways  in  which  the 


Fig.  128. 


Fig.  129. 

Figs.  128  and  129.— Bracket 
Casting. 


Fig.  131. 

Figs.  130  and  131.— Bracket  Casting 
Pattern,  with  Core-prints. 


pocket  prints  may  be  arranged,  and  the  choice  of  either 
depends  very  much  on  relative  dimensions,  degree  of 
accuracy  required,  moulding  flasks  available,  custom  of  a 
given  workshop,  etc.  One  method  is  as  follows :  First,  the 


CORING  HOLE 8  IN  CASTINGS. 


77 


foot  may  be  jointed  in  pattern  and  mould  on  a  level  with 
the  top  face  A  of  the  web,  just  as  shown  in  Fig.  130,  in 
which  case  one  portion  of  the  foot  will  go  in  the  bottom 
and  the  other  in  the  top  of  the  mould.  Then  the  pocket 
prints  will  be  arranged  as  in  Figs.  130  and  131,  one  print  to 
each  hole,  the  tapering  being  away  from  the  joint  B. 

A  truer  plane  face  is  ensured  to  the  foot  of  the  bracket 
by  leaving  it  unjointed  (Figs.  132  and  133),  making  only  the 
top  rib  A  loose,  so  carrying  the  moulder's  joint  up  to  the 
top  edge  of  the  foot,  and  fastening  on  the  required  pocket 
prints  to  lift  from  the  top  edge,  covering  both  holes,  as  in 
Figs.  132  and  133.  A  third  method  is  to  use  a  single  print 
and  core-box,  as  in  Fig.  121  and  Figs.  124  and  125  (pp.  73 


Fig.  132.  Fig.  133. 

Figs.  132  and  133.— Alternative  Method  of  Arranging  Pocket  Prints, 

and  74).  Whenever  practicable,  the  method  shown  in 
Figs.  132  and  133  is  the  best  to  adopt,  but  with  a  single 
print  only,  a  more  accurate  face  being  ensured  than  when 
a  moulder's  joint  is  carried  across  it. 

Continuing  the  consideration  of  pocket  prints,  take  the 
case  of  a  piece  of  pipe  in  the  flanges  of  which  square  holes 
have  to  be  cast  (Figs.  134  and  135).  The  pipe  has  to  be 
moulded  horizontally,  and  the  holes  therefore  cannot  be 
cored  with  common  tapered  prints,  but  must  be  formed  with 
horizontal  cores.  Prints  must  therefore  be  of  the  pocket 
type,  and  they  need  only  be  fastened  on  one  face  of  the 
flange,  because  they  have  to  bridge  but  a  narrow  space. 
Figs.  136  and  137  show  the  pattern  for  one  of  the  flanges 
fitted  with  its  prints.  That  the  shapes  of  their  ends  exactly 


PRACTICAL  PATTERN  MAKING. 


agree  with  the  corresponding  forms  of  the  holes  which  they 
have  to  core  is  clear  on  a  comparison  with  Figs.  134  and  135. 
All  the  portions  of  the  print  impressions  above  the  cores 
have  to  be  stopped  over,  and  this,  of  course,  is  completed 


Fig.  135. 
Figs.  134  and  135.— Pipe  Casting  with  Square  Holes  in  Flanges. 

before  the  insertion  of  the  main  central  core  in  the  print  im- 
pression formed  by  A.  The  cored-up  mould  is  seen  com- 
pleted in  Fig.  138. 


Fig.  136.  Fig.  137. 

Figs.  136  and  137.— Pattern  of  Flange  with  Prints  for  Pipe  Casting. 

It  is,  however,  common  practice  to  locate  the  positions 
of  small  cores  in  flanges  without  the  use  of  prints  at  all. 
The  cores  are  then  set  by  means  of  a  gauge  or  template, 
called  a  stopping-over  piece,  shown  in  Fig.  139.  The  cores 


CORING  HOLES  IN  CASTINGS. 


are  lowered  down  into  approximate  position  by  means  of 
the  moulder's  cleaner,  and  then  set  exactly  by  the  lowering 
down  of  the  stopping-over  piece  above  them.  This  is  illus- 
trated in  Fig.  140,  A  A  being  cores,  and  B  the  stopping-over 
piece.  The  cores  are  retained  in  position  wholly  by  friction 
against  the  faces  of  the  flanges,  so  that  they  are  made  a 
little  full  in  length.  Sometimes  a  nail  is  forced  into  the 
sand  over  the  cores  to  prevent  the  chance  of  their  rising 
up  by  the  flow  of  metal.  But  this  is  not  desirable,  nor  is 
it  necessary  if  the  cores  fit  well. 

Figs.  141,  142,  and  143  show  examples  of  pocket  prints 


Fig.  139. —Stopping-over  Piece 
used  without  Prints. 


Fig.  138.— Mould  for  Pipe  Casting, 
with  Cores  Inserted. 


Fig.  140. — Stopping-over 
Piece  in  Use. 


for  coring  slot  holes.  Figs.  141  and  142  are  two  views  of 
a  bracket  having  slot  holes  A  A  cored  in  the  foot.  In  Fig. 
143,  the  pocket  prints  A  A  for  these  are  shown  nailed  on  the 
bottom  of  the  foot.  Here,  as  in  previous  examples,  it  is 
seen  that  the  shape  of  the  end  of  the  prints  coincides  with 
the  shape  and  position  of  the  lower  portion  of  the  holes,  as 
the  pattern  moulds.  In  this  example,  too,  as  in  Figs.  136 
and  137,  the  coi-es  may  be  made  of  the  exact  shape  of 
the  holes  and  stopped  over.  Or  the  core-box  may  be  so 
made  that  the  cores  shall  stop  themselves  over  in  the 
manner  previously  described. 

Cases  occur  in  which  horizontal  prints  which  may  or 


«0 


PRACTICAL  PATTERN  MAKING. 


may  not  be  of  the  pocket  form  are  used  to  enable  several 
similar  small  castings  to  be  cored  out  at  once  with  a  single 
core.  Fig.  144  is  illustrative  of  the  method.  In  this  case 
four  distinct  pieces  A  A  A  A  are  connected  with  prints 
B  B  B  B,  and  one  core  laid  along  the  whole  length  cores  the 


Fig.  141. 


Fig.  142. 


Fig.  143. 


Figs.  141  and  142.— Bracket  Casting  with  Slot  Holes  in  Foot. 
Fig.  143.— Prints  on  Foot  of  Bracket  Pattern. 

four  castings  at  once.  Time  is  saved  in  moulding  and  in 
coring,  and  greater  accuracy  is  ensured  than  if  one  pattern 
only  were  moulded  and  cored  at  once.  In  some  classes  of 
patterns,  pocket  prints  would  be  found  most  suitable. 


B  I    I         lit; 
Fig.  144. — Patterns  United  with  Continuous  Print. 

These  and  similar  examples  of  coring  might  be  multi- 
plied ;  one  example  will  be  noted,  which  is  of  a  large  type, 
and  in  which  the  reason  for  coring  would  not  be  obvious  to 
a  person  unacquainted  with  the  details  of  moulding.  This 
is  coring  which  is  not  always  absolutely  necessary,  since 


CORIXG  HOLES 


CASTINGS. 


81 


there  would  be  other  possible  ways  of  moulding,  but  which 
is  most  convenient  and  desirable.  Thus  the  double  bracket 
(Figs.  145  and  146)  would  be  a  troublesome  job  for  the 
moulder  if  the  pattern  were  made  like  the  casting,  because 


L 


Fig.  H  5. —Double  Bracket  Casting. 

of  the  central  space  A.  The  best  way  would  be  to  joint 
both  pattern  and  mould  along  the  plane  A.  But  if, 
instead  of  a  central  rib  B,  there  were  ribs  around  the 
sides  at  c  C,  as  shown  dotted,  then  the  pattern  could  not  be 
jointed  at  A.  Many  such  cases  occur  in  which  it  is 


Fig.  H6.— Double  Bracket  Casting. 


desirable  to  take  out  the  central  portion  A  with  a  core,  the 
pattern  being  made  as  in  Figs.  147  and  148 ;  the  pattern  h. 
jointed  upon  the  print  A  at  B  B,  all  above  that  plane  being 
dowelled  to  be  lifted  with  the  top  of  the  mould.  A  core- 
box  has  to  be  made  to  suit  the  print  impression. 
F 


82 


PRACTICAL  PATTERN  MAKING. 


The  foregoing  examples  will  suffice  to  indicate  the 
typical  methods  which  are  employed  for  the  coring  of  holes 
in  castings.  Not  only  are  small  holes  cored,  but  large 
spaces  are  taken  out  in  the  same  manner  in  order  to 


rig.  147.    i 


148. 


Figs.  147  and  148.— Double  Bracket  Pattern. 

simplify  the  work  of  moulding,  and  to  ensure  castings  more 
accurate  than  could  be  obtained  by  self-delivery.  The 
principles  which  have  been  laid  down  may  be  studied  with 
advantage  and  extended  into  many  details. 


83 


CHAPTER  VII. 

PATTERNS  AND   MOULDS  FOR   IRON  COLUMNS. 

As  in  the  previous  chapter,  it  is  thought  advisable  to  give 
information  here  on  some  matters  not  strictly  coming 
under  the  particular  heading  of  pattern-making.  It  was 
pointed  out  in  the  first  chapter  that  the  successful  pattern- 
maker must  have  a  knowledge  of  many  operations  and 
processes  outside  his  own  special  department ;  and  it  is 
with  that  in  mind  that  the  scope  of  the  information  here 
presented  has  been  broadened.  Besides  the  actual 
making  of  the  patterns,  this  chapter  will  give  some  in- 
formation on  the  subsequent  processes  of  moulding  and 
casting. 

In  the  accompanying  figures,  Fig.  149  is  a  plan  of  the 
complete  pattern  for  an  iron  column  ;  Fig.  150  is  a  plan 
of  half  the  pattern  opened  in  the  joint  face  ;  Fig.  151  is  a 
cross  section  through  the  body  taken  on  the  dotted  line  in 
Fig.  150 ;  Fig.  152  is  an  end  view  of  half  the  print  at  the 
large  end  ;  Fig.  153  is  a  similar  view  of  half  the  print  at 
the  small  end. 

There  is  no  difference  in  the  method  of  constructing 
the  column  pattern  when  cast  horizontally  or  vertically. 
It  is  unusual  to  cast  such  columns  on  end.  Large  pipes 
are  so  cast  in  the  regular  pipe-shops,  where  there  are 
special  and  costly  jigs  for  the  purpose.  A  column  that 
has  to  be  cast  on  end  is  moulded  in  the  same  way  as  a 
column  to  be  cast  horizontally — that  is,  in  an  ordinary 
two-part  flask,  with  round  holes  at  the  ends  for  the  core- 
bar  to  pass  through,  and,  in  addition,  two  extra  holes  at 
the  top  end,  one  to  pour  the  metal  in,  and  one  for  a  riser 
or  flow-off  gate,  the  latter  being  necessary  to  ensure  a 
clean  top  face. 

If  there  is  anything  very  special  in  the  specification 
as  to  the  soundness  of  the  metal,  it  will  be  better  to  add 
8  in.  or  10  in.  of  head  metal  to  the  pattern.  But  this  is 
not  necessary  for  ordinary  good  work.  After  the  pattern 
is  moulded  in  the  ordinary  way  and  cored  up,  the  flasks 


PRACTICAL  PATTERN  MAKING. 


Fig.  H9.  Fig.  150. 

Figs.  149  and  150.— Column  Pattern  and  Half  Pattern. 


PATTERNS  AND  MOULDS  FOR  IRON  COLUMNS.   85 

are  cottered  together,  lifted  on  end  and  lowered  into  the 
pit  for  casting  vertically. 

The  illustrations  show  a  pattern  just  as  it  would  be  made, 
though,  of  course,  modified  methods  are  practicable.  For 
example,  such  patterns  are  sometimes  lagged  only  as 


Fig.  131.— Cross  Section  of  Column  Pattern. 

far  as  the  inner  faces  of  the  flanges ;  these  are  then 
screwed  directly  on  the  pattern  ends,  and  the  prints  on 
those.  Slightly  thinner  stuff  may  then  be  employed  for 
the  lagging,  but  it  is  not  desirable  to  use  very  thin  stuff. 
Sometimes  the  pattern,  though  lagged  continuously  as 
shown,  has  long  blocks  at  the  ends  instead  of  the  narrow 
bridges  for  lagging  on.  This  makes  the  ends  stronger. 
But  the  method  showrn  is  the  best  on  the  whole. 

The  blocking  pieces  A  (Figs.  150  and  151)  are  first 
dowelled  together,  marked  out,  and  the  facets  planed. 
Half  the  pieces — those  with  the  dowel  holes — will  then 
be  laid  down  upon  a  true  bench  or  plank  arranged  by 
means  of  their  centre  lines,  and  at  suitable  distances  apart. 
Tack  them  down  with  brads,  checking  their  truth  with  a 
straightedge.  Then  prepare  the  lagging  strips  with  saw 


Fig.  152.  Fig.  153. 

Figs.  152  and  153.— Large  and  Small  Ends  of  Column  Pattern. 

and  plane,  and  fit  each  strip  to  its  facet.  The  two  strips 
next  the  joint  face  will  be  fitted  first,  and  afterwards  the 
two  above.  Each  joint  face  must  be  fitted  to  its  fellow, 
using  chalk  to  check  the  perfect  contact  necessary  to  a 
good  joint,  and  each  is  glued  to  its  fellow  and  also  to  the 


86  PRACTICAL  PATTERN  MAKING. 

facets  upon  which  it  lies.  The  glue  joint  will  be  rubbed 
by  two  men,  one  near  each  end,  and  a  screw  will  be  run 
through  the  lagging  into  each  facet  of  the  blocks  A.  When 
one  half  is  thus  glued  up  it  is  lifted  off  the  board,  turned 
on  its  back,  the  complementary  halves  of  the  blocks  A 
dowelled  on,  and  the  remaining  half  of  the  lagging  fitted 
and  glued — omitting  glue,  of  course,  in  the  joint  face  of 
the  pattern. 

The  two  halves  are  now  held  together  with  centre-plates 
screwed  in  the  ends,  and  the  pattern  turned  in  the  lathe. 
The  two  ends  are  turned  first  to  the  dimensions  required, 
and  then  one  flat  is  planed  from  end  to  end,  making  a 
tangent  level  with  the  turned  ends.  This  flat  being  chalked, 
or  rubbed  with  red  lead,  is  a  safe  guide  for  turning  down 
the  remainder  of  the  pattern  without  any  guess  or  trial,  in- 
volving frequent  stoppage  of  the  lathe  and  trial  with  a 
straightedge. 

The  turning  of  the  prints  and  the  grooves  for  the  flanges 
follows.  The  flanges,  though  rectangular,  should  have 
their  hollows  turned  as  shown.  This  can  be  done  on  a 
face-plate.  The  stiffening  brackets  are  fitted  finally. 
Those  in  the  joint  need  not  be  divided  in  halves,  but  made 
of  full  thickness  and  screwed  to  one  half  the  pattern  only. 
Rapping  and  lifting-plates,  though  not  shown,  should  be 
put  in  the  joint  faces.  They  are  best  let  into  the  cross- 
bars. 

Figs.  154  to  158  illustrate  the  moulding  of  a  column  18  ft. 
long  and  14  in.  in  diameter,  with  1%-in.  metal.  The  illustra- 
tions are  not  strictly  proportionate,  the  length  being 
slightly  lessened  in  order  to  economise  space,  thus  giving 
larger  proportion  to  the  diameter,  with  clearer  detail. 

To  cast  a  column  of  1^  in.  thickness  of  metal  is  not  so 
troublesome  as  to  cast  one  |  in.  or  1  in.  thick,  because  in 
the  former  case  there  is  less  risk  of  getting  the  metal  thin 
or  blown.  It  is  easier  to  cast  a  column  of  large  than  of 
small  diameter. 

There  are  two  or  three  ways  of  making  columns ;  the 
choice  depends  on  the  number  required.  The  illustrations 
show  the  method  employed  when  only  a  few  castings  are 
required.  In  this  case  a  pattern  is  used,  jointed  down  the 
centre,  and  rammed  with  or  without  the  assistance  of 
a  bottom  or  joint-board.  The  use  of  the  joint-board, 


87 


s'8 1 


c 


88  PEAGTICAL  PATTERN  MAKING. 

however,  is  very  desirable,  because  it  keeps  the  pattern 
straight,  and  its  joint  in  line  with  the  joint  of  the  moulding 
box. 

In  a  proper  column  box  there  is  no  difference  in  the 
shape  of  the  top  and  bottom  parts  ;  each  has  vertical  bars 
or  stays  cut  to  follow  the  column  sections  at  a  distance 
of  I  in.  away  from  its  body.  But  a  flask  with  flat  bars  in 
one  half  and  vertical  bars  in  the  other  will  also  answer 
very  well,  the  flat  stays  being  in  the  bottom  at  the  time  of 
casting.  The  top  ones  will  have  to  be  well  shaped,  as 
shown  in  Fig.  155,  to  retain  the  sand. 

To  mould  the  column  without  a  bottom  board,  the 
flask,  which  is  to  be  finally  the  cope,  will  be  filled  with 
loose  sand,  into  which  one-half  the  pattern  will  be  bedded, 
and  its  face  strickled  level  with  the  "flask  joint.  Upon 
this,  strewn  with  parting  sand,  the  second  half  of  the  pat- 
tern will  be  rammed  permanently  in  that  half  which  is  to 
be  the  drag  flask.  Turning  the  flask  over,  the  first  half 
will  be  taken  off,  its  sand  knocked  out,  and  the  half  pat- 
tern removed.  The  drag  joint  will  be  strickled  and  parting 
sand  strewn  over  it,  the  half  pattern  and  the  top  put  back, 
the  sand  put  in  and  rammed.  Then  the  flask  will  be  parted, 
the  pattern  drawn,  and  the  mould  mended  and  blackened 
in  readiness  for  the  core.  Fig.  154  shows  the  drag  as  it 
appears  when  ready  to  receive  the  top  part. 

A  column  may  also  be  moulded  with  a  half  flask  only, 
as  is  often  done  in  jobbing  work,  one-half  the  pattern 
being  bedded  in  the  floor  and  a  top  part  flask  set  over  it, 
guided  into  position  with  corner  stakes.  This  is  a  handy 
method  when  pairs  of  flasks  are  not  available,  and  when 
the  job  will  not  pay  for  their  making.  Extra  care,  how- 
ever, has  to  be  taken  in  tucking  and  ramming  under,  to 
guard  against  risk  of  a  lumpy  casting. 

One  cannot  readily  go  wrong  in  making  the  mould,  but 
trouble  may  arise  in  connection  with  its  coring.  Fair, 
careful  ramming  and  sufficient  venting  will  secure  a 
good  mould.  In  the  coring,  the  core  must  be  both  made 
and  set  properly.  The  causes  of  waster  castings  more 
often  lie  in  the  coring  than  in  the  moulding. 

In  jobbing  work,  cores  are  swept  up  on-  hollow  bars  or 
arbors,  which  are  pierced  with  hundreds  of  holes  to  per- 
mit the  air  from  the  vents  to  pass  into  the  interior  and 


PATTERN'S  AND  MOULDS  FOB  IRON  COLUMNS.   89 


out  at  the  ends.  The  relative  diameters  of  bar  and  core 
vary  considerably.  In  foundries,  bars  of  many  diameters 
and  lengths  are  stocked,  and  the  one  which  happens  to 


come  nearest  to  the  size  required  is  selected,  so  that  it 
may  often  happen  that  some  hay-band  is  wasted  in  con- 
sequence of  the  bar  selected  being  rather  small.  The 
smaller  the  thickness  of  band  and  loam  on  a  bar  the  better. 


90  PRACTICAL  PATTERN  MAKING. 

bands  and  the  core  maker's  time  being  thus  economised. 
From  1  in.  to  l£  in.  is  a  minimum  allowance. 

To  sweep  up  a  core,  the  bar  or  arbor  is  revolved  on  the 
trestles,  while  the  core  maker  pulls  the  hay  rope  taut, 
moving  along  the  bar  as  the  hay  becomes  wound  around 
it;  whilst  coarse,  stiff  loam  is  daubed  among  and  over  the 
bands  to  bring  the  core  nearly  up  to  diameter.  It  is  then 
partially  dried  previous  to  the  daubing  on  and  finishing  of 
the  final  coat  of  loam,  which  is  then  dried  and  black- 
washed.  No  venting  with  the  wire  is  necessary,  because 
the  hay  or  straw  ropes  are  sufficiently  porous  to  be  self- 
venting.  The  core  must  be  thoroughly  dried  in  the  stove 
before  being  inserted  in  the  mould,  for  if  it  is  not  dry  at 
the  time  of  pouring,  the  casting  will  become  blown.  This 
is  an  important  point,  since  cores  are  sometimes  put  into 
the  mould  so  long  before  the  pouring  can  be  done  that 
they  absorb  moisture,  and  cause  risk  of  an  unsound  or 
waster  casting. 

The  core  is  not  shown  separately,  nor  in  full  detail, 
the  hay-bands  being  omitted.  Fig.  155  will,  however,  show 
what  is  wanted.  The  core  bar  is  long  enough  to  come 
through  the  ends  of  the  mould,  to  convey  the  air  away. 
The  hay-bands  wound  around  it  (not  indicated  separately) 
will  be  thinly  laid  along  its  body,  but  increased  in  thick- 
ness at  the  base  and  cap,  where  the  metal  spreads  out, 
because  where  thickness  of  core  has  to  be  increased  it 
should  be  done  with  bands  and  not  with  loam,  which  should 
not  anywhere  exceed  from  \  in.  to  £  in.  The  bands  lie  in 
contact  with  the  bar  right  along  the  vents,  through  which 
the  air  passes  into  the  numerous  holes  seen  in  the  sectional 
view. 

At  the  right-hand  end,  the  base,  which  is  square,  has 
to  be  lightened  with  a  square  core  B.  This  is  made  in 
a  box  having  a  cenfcral  print  of  a  definite  size,  to  suit  the 
shoulder,  which  is  struck  on  that  end  of  the  main  core,  as 
shown  in  Fig.  155.  The  square  core  then  fits  over  the 
shouldered  end.  The  vents  from  it  are  brought  into  the 
main  core,  and  so  out  at  the  end  of  the  bar. 

Fig.  155  is  a  sectional  view  of  the  mould  taken  in  the 
vertical  plane.  Fig.  156  is  a  plan  view  of  the  mould 
opened  in  the  joint,  with  the  core  fixed  ;  and  Fig.  157  is 
a  cross-section  taken  in  the  centre.  These  illustrate  the 


PATTERNS  AND  MOULDS  FOR  IRON  COLUMNS.  91 

fixing  of  the  core,  and,  with  Fig.  158,  the  pouring  arrange- 
ments. 

With  reference  to  the  fixing  of  the  core,  the  print  im- 
pressions hold  it  at  the  ends,  and  of  course  they  should 
secure  it  centrally  in  the  mould.  But  it  is  not  wise  to 
take  this  for  granted.  When  a  core  is  inserted  in  print 
impressions,  the  thickness  of  space  must  be  tried  at  the 
top  and  bottom  in  two  or  three  places  with  clays,  the 
flasks  being  closed  on  the  clays,  and  on  their  separation 
the  thicknesses  to  which  the  clays  will  have  been  squeezed 
will  show  the  thickness  of  space  between  core  and  mould 
for  the  metal.  In  the  joints,  the  thicknesses  at  the  sides 
can  be  measured  directly  with  a  rule. 

It  may  seem  strange  to  anyone  but  a  moulder  that  this 
measurement  should  be  necessary  with  a  circular  core  in 
a  circular  mould.  But  inaccuracies  creep  in  whilst  the 
pattern,  mould,  and  core  are  being  made.  Prints  get  out 
of  centre,  patterns  out  of  truth  circularly  and  lengthwise, 
and  cores  sag  by  their  own  weight.  The  object  of  check- 
ing, therefore,  is  to  afford  the  moulder  a.  chance  of  correct- 
ing these  inaccuracies. 

Although  the  core  is  secured  centrally  by  the  ends,  this 
would  not  retain  it  in  the  central  position  when  the  pres- 
sure of  metal  acts  upon  it,  when  it  would  be  forced  upwards, 
causing  the  metal  to  be  thinner  in  the  top  than  in  the 
bottom  ;  it  might  also  move  sideways.  Chaplets  are  there- 
fore used  to  prevent  these  movements.  These  are  tinned 
nails  c  c,  the  heads  of  which  abut  against  the  core, 
and  the  points  against  the  flask  sides,  and  in  top  and 
bottom  against  stays  or  plates,  or  driven  into  blocks 
of  wood  rammed  in  the  sand.  In  columns  having  thin 
metal,  these  stays  must  be  more  numerous  than  in  those 
of  heavier  section.  In  a  column  with  1^-in.  metal,  four 
chaplets  at  the  centre,  as  shown,  are  sufficient. 

The  pouring  of  columns  is  done  in  various  ways.  If 
the  metal  is  thin,  they  are  poured  from  a  long  thin  runner 
•on  top,  or  from  a  spray  or  sprays  at  the  sides,  as  well  as 
from  the  ends.  When  the  metal  is  thick,  as  illustrated, 
they  are  poured  from  the  ends.  Here,  too,  the  metal  can 
be  brought  in  at  the  edges  of  the  flanges,  or  at  their  ends, 
or  on  top.  It  really  matters  little  which  is  adopted,  and 
often  the  question  is  settled  by  the  presence  or  absence 


92  PRACTICAL  PATTERN  MAKING. 

of   bolt  cores   in   the   flanges,    and   of   faced   or   unfaced 
portions. 

In  Figs.  155  and  158  the  mould  is  shown  poured  against 
the  faces  of  the  flanges  and  at  both  ends  simultaneously, 
the  column  being  long.  Pouring  basins  c,  c  are  rammed 
on  the  top  flask  to  suit  runner  pins  previously  rammed  up 
with  the  pattern.  The  horizontal  runners  seen  in  Fig.  155 
carry  the  metal  in  an  uninterrupted  flow  between  the  core 
and  the  mould,  the  streams  meeting  in  the  middle  before 
the  iron  has  time  to  become  chilled.  Over  each  flange  a 
riser  D  is  often  set,  and  one  or  two  are  set  at  intervals 
along  the  length,  their  purpose  being  to  relieve  the  mould 
of  strain,  and  to  take  any  dirt  taken  up  from  the  mould. 


CHAPTER   VIII. 

STEAM-ENGINE   CYLINDER  PATTERNS  AND   CORE-BOXES. 

WHEN  steam-engine  cylinders  of  from  about  4-in.  to  8-in. 
bore  are  designed  as  shown  in  Figs.  159  to  161,  so  small  a 
portion  of  the  outer  part  of  the  pattern  is  cylindrical,  and 
the  advantage  of  lagging  is  so  slight,  that  the  method  of 
pattern-making  shown  in  Fig.  162  is  best.  The  half  pattern 
as  shown  here  is  built  of  ten  slices,  including  flanges  and 
core  prints.  Neglecting  the  prints,  the  slices  are  made  to 
thickness,  jointed,  and  screwed  together,  glue  not  being 
used  in  these  joints.  The  dowelled  joint  between  the 
halves  is  now  made,  and  on  one  half  of  the  pattern  the 
outline  of  the  section  is  marked  with  the  line  of  the  joint 
for  the  steam-chest  flange  A  (Fig.  162).  Fig.  163  is  a  section 
on  G  H  (Fig.  162). 

The  D-shaped  outlines  of  the  cylinder  flanges  are 
marked  on  the  ends,  and  the  positions  of  the  pieces  noted 
by  pencilling  a  letter  or  number  on  each  part.  The  centre 
line  of  the  bore  is  scribed  on  each  half,  the  faces  A  and  B 
(Fig.  160)  of  the  steam  inlet  and  outlet  are  planed  and 
their  shapes  struck  out,  and  the  whole  is  taken  to  pieces 
afterwards. 

By  the  aid  of  compasses  and  square  now  mark  the 
section  of  each  slice,  which  may  then  be  brought  to  shape 
with  band  saw  or  bow  saw,  chisel,  and  gouge.  Then  the 
slices  may  be  glued  and  screwed  together,  a  light  cleaning- 
up  of  the  body  over  the  joints  being  done  before  the  flanges 
are  finally  fixed. 

The  body  prints  B  (Fig.  162)  are  turned  in  halves  and  a 
fla.t  portion  is  cut  on  the  lower  half,  in  this  case  the  half 
attached  to  the  part  with  the  inlet  branch.  The  flat  is 
worked  into  the  circle  with  a  considerable  taper,  so  that 
the  core  does  not  press  on  the  mould  until  it  takes  its 
final  bearing.  The  taper  print  c  (Figs.  162  and  163)  is  for 
the  core  of  the  inlet  chamber  c  (Fig.  160).  The  circular 
print  D  (Fig.  162)  with  a  stalk  is  in  halves  (one  for  each 
half  of  the  pattern)  for  the  core  that  forms  the  valve 


PRACTICAL  PATTERN  MAKING. 


STEAM-ENGINE  CYLINDER  PATTERNS. 


95 


spindle  stuffing-box.  This  print  should  be  long  enough 
to  allow  the  core  to  lie  in  position  without  over-balancing 
into  the  mould.  The  print  E  (Fig.  162)  for  the  steam-chest 
core  has  a  sharp  taper,  so  that  when  the  mould  is  made  the 
top  box-part  may  be  lowered  upon  it,  without  touching  the 
core  until  the  mould  is  closed. 


The  pattern  may  be  glass-papered  and  shellac-var- 
nished, a  stiff  rapping  and  lifting  plate  being  let  in  each 
half  on  the  joint,  and  the  transverse  section  marked  in 
black  varnish  on  one  half  as  a  guide  to  the  moulder  in 
arranging  the  cores.  The  prints  should  be  finished  and 
varnished  black  before  being  fastened  on  the  pattern. 


96 


PRACTICAL  PATTERN  MAKING. 


The  body  core-box  (Figs.  164  and  165)  is  built  up, 
dowelled,  and  stiffened  with  transverse  pieces  or  backing  E 
(Fig.  165).  The  ends  are  cleaned  off  to  length,  a  centre  line 
is  gauged  on  one  half,  the  bore,  less  about  f  in.  for  tooling, 


m 


Fig.  164.  Fig.  165. 

Figs.  164  and  165.— Half -body  Core-box  for  Small  Steam  Cylinder. 

being  struck  on  each  end,  and  the  circular  section  (neglect- 
ing the  counter-bore)  worked  through  and  finished  with  a 
round-sole  plane.  The  blocks  B  (Fig.  164)  are  fitted  in  to 
match  the  flattened  parts  of  the  core  prints,  and  the  prints 


Jj'ig.  Kill.  i'ig.  167. 

Figs.  166  and  167.— Half  Core-box  for  Exhaust  Port. 

r  (Figs.  164  and  165)  are  attached  to  give  the  bearing  for 
one  end  of  the  steam  passage  core.  This  rests  on  the 
impression  of  the  lower  part  of  D  (Fig.  165),  which  is 
fixed  in  the  half  of  the  box  not  shown.  The  bearing  part 


STEAM-ENGINE   CYLINDER  PATTERNS.          07 

is  shown  some  distance  below  the  joint  of  the  mould,  and 
D  will  project  into  the  opposite  part  of  the  core-box.  The 
latter  carries  no  ends,  as  it  is  better  to  clamp  the  two  parts 
of  the  box  together,  and  to  ram  the  core  as  a  whole. 

Figs.  166  and  167  show  the  box  for  the  core  to  produce 


the  exhaust  port  and  passage  shown  in  Fig.  160.  Fig.  167 
is  a  section  on  G  H  (Fig.  166).  A  (Fig.  167)  shows  by  dotted 
lines  the  template  used  to  obtain  the  shape  of  the  box 
corresponding  to  B  (Fig.  159).  This  template  is  moved 
radially  around  the  curve  B  (Fig.  166).  c  (Fig.  166)  may  be 
circular  in  section,  as  shown  by  the  dotted  lines  in  Fig. 
G 


98 


PRACTICAL  PATTERN  MAKING. 


167,  or  D-shaped,  like  the  steam-inlet.  The  part  D  (Fig. 
166)  fits  the  impression  in  the  top  box  made  by  a  print  on 
the  face  B  (Fig.  160).  The  end-piece  E  (Fig.  166)  stops  the 
core-box,  each  half  core  in  this  case  being  separately 
rammed,  and  afterwards  fastened  together.  B  (Fig.  167) 
shows  the  backing  which  is  glued  and  screwed  on  the  box. 
Figs.  168  to  170  show  the  core-box  for  taking  out  the 
steam  chest,  Fig.  169  being  a  section  on  G  H  (Fig.  168),  and 
to  understand  the  part  F  (Fig.  166),  reference  should  be 
made  to  A  (Figs.  168  and  170),  which  is  the  core  print 
corresponding  to  this  part.  The  main  part  of  the  box 
consists  of  a  frame,  housed  together  but  not  glued,  for  it 
is  necessary  to  separate  the  parts  after  the  core  is  rammed. 
The  upper  part  of  the  box  matches  the  print  E  (Fig.  162), 


Fig.  171.  Fig.  172. 

Figs.  171  and  17:?. — Steam-inlet  Core-box. 

and  this  part  of  the  core  should  be  heavy  enough  to  prevent 
the  overhanging  part  falling  into  the  mould.  The  piece 
c  (Fig.  168),  permanently  fastened  to  the  flat  bottom 
board  E,  gives  the  shapes  of  the  valve  face  and  the  convex 
back  of  the  metal  separating  the  steam  chest  from  the 
passages,  as  at  A  (Fig.  161).  A  and  B  (Figs.  168  and  170) 
are  prints  fitted  loosely  into  grooves  so  that  each  may  be 
drawn  separately  from  the  core.  A  is  as  wide  as  the 
exhaust  port,  less  an  amount  (say  J.r  in.)  on  each  side  for 
chipping  and  filing,  while  B  for  the  steam-port  prints  should 
have  similar  allowances.  One  end  of  each  of  these  prints 
touches  the  facing  D  (Fig.  168),  as  the  port  cores  are 
lowered  into  the  mould  after  the  body  core  and  steam-chest 
core  are  in  place.  The  other  ends  are  best  cut  short  of  the 
width  of  the  steam  passages  to  obtain  increased  thickness 
of  sand  in  the  steam-chest  core  to  support  the  port  cores. 


STEAM-ENGINE  CYLINDER  PATTERNS.          19 

The  valve  face  should  allow  about  \  in.  for  tooling.  F  (Fig. 
168)  is  an  extension  of  the  flange  of  the  steam-chest,  and 
forms  a  stuffing-box  for  the  valve  spindle  D  (Fig.  160). 

Fig.  171,  with  Fig.  172,  which  is  a  section  on  c  D, 
shows  a  core-box  made  of  two  pieces  of  wood  dowelled  on 
the  joint  A  B.  This  box  is  for  the  steam  inlet  chamber  c 
(Fig.  160).  The  part  c  (Fig.  172)  corresponds  to  the  print 
c  (Figs.  162  and  163).  From  c  (Fig.  160),  which  gives  a 


H 
Fig.  176. 

Figs.  173  to  176.— Steam-port  Core-box. 


Fig.  173. 


section  of  the  core  at  right  angles  to  that  of  Fig.  172,  the 
contour  of  the  upper  face  of  the  core-box  may  be  obtained. 
This  contour  is  transferred  to  the  core  by  drawing  a 
straight  strickle  across  the  box  after  the  ramming  is  com- 
pleted. One  part  is  in  contact  with  the  steam-chest  core, 
and  this  part  cores  out  the  oblong  opening  c  (Fig.  159). 

Figs.  ]73  to  176  show  the  steam-port  core-box,  Fig.  174 
being  a  section  on  c  D  (Fig.  173).  A  block  A  (Figs.  173, 
174,  and  176)  has  an  upper  surface  corresponding  to  the 
convexity  of  the  steam  passage  B  (Fig.  161).  The  core  is 


100 


PRACTICAL  PATTERN  MAKING. 


rammed  upon  this,  and  the  upper  surface  of  the  sand 
brought  to  shape  by  drawing  the  strickle  B  (Fig.  173) 
across  two  guiding  surfaces  E  and  F  (Fig.  173).  G  (Figs. 
173  to  176)  partly  forms  the  steam-port  core,  and  is  fastened 
to  the  two  vertical  pieces  H  (Figs.  174  to  176)  screwed  on 
M  (Fig.  176).  Both  the  steam-port  cores  are  made  from 
this  box,  but  as  they  are  not  exactly  similar,  two  loose 
pieces  J  and  K  (Figs.  174  to  176)  are  provided.  J  is  also 
shown  in  Figs.  177  and  178.  One  core  is  rammed  with  J 
and  K  in  the  positions  shown  ;  then  before  the  other  core 
is  made  the  pieces  are  changed  to  the  other  side  of  the 


Fig.  17'J. 


Fig.  177. 


Fig.  178.       ll\j\ll 

Figs.  177  and  178.— Loose  Piece 
for  Valve  Spindle  Stuffing-box. 


Fig.  180. 


iffs.  179  and  180.— Half  Core-box 
for  Valve  Spindle  Stuffing-box. 


box.  The  bearing  part  of  the  passage  core  upon  the  steam- 
chest  core  is  formed  by  J,  and  this  enters  the  impression  of 
the  print  B  (Fig.  170),  the  bearing  part  of  the  passage  core 
in  the  body  core  being  formed  by  K. 

The  side  pieces  M  are  divided  along  A  B  (Fig.  175),  the 
portions  to  the  left  of  this  line  together  with  the  pieces 
N  and  G  (Fig.  176)  being  connected  to  form  a  frame  which 
is  fitted  loosely  over  the  block  A.  L  (Figs.  173  and  176)  is 
a  small  block  fitted  to  the  backing  o  (Fig.  173)  to  keep  this 
frame  in  place  whilst  the  core  is  rammed.  Finally,  Figs. 
179  and  180  show  the  core-box  for  hollowing  out  the  valve 
spindle  stuffing-box. 


101 
CHAPTER  IX. 

WORM   WHEEL  PATTERN. 

To  make  accurate  patterns  for  worm  wheels,  it  is  almost 
necessary  to  have  the  worm  cut  first.  It  is  possible,  at  a 
great  expenditure  of  time,  to  mark  off  the  teeth  directly 
from  a  drawing  which  shows  a  section  of  the  thread  of 
the  worm,  and  to  work  to  the  lines  so  struck.  But  such 
time  is  grudged  in  the  shops,  neither  is  the  method  so 
accurate  in  practice  as  the  one  about  to  be  described.  It 
is  to  have  the  worm  cut,  and  to  make  it  the  gauge  for 
checking  the  correspondence  of  the  wheel  teeth  therewith 
in  all  positions  of  the  worm  and  wheel  during  their 
movements. 


Fig.  181.—  Worm  Casting. 

The  method  in  principle  is  precisely  that  which  is 
adopted  for  cutting  or  "  hobbing  "  the  metal  teeth  of  worm 
wheels.  In  this  method  a  steel  worm  is  made,  and  then 
the  thread  is  serrated  at  intervals,  and  backed  off  behind 
each  serration,  much  like  a  master-tap ;  and  this,  when 
hardened,  is  used  to  cut  the  worm  wheel.  There  need  be  no 
trouble  experienced  in  getting  the  worm  made  before  the 
wheel  is  made  ;  for  it  is  always  necessary  to  fix  the  dimen- 
sions of  the  worm  before  the  wheel  can  be  marked  out,  and 
if  the  worm  is  cast  it  can  be  cast  first ;  if  forged,  it  can  be 
cut  in  the  lathe  first. 

Having  the  worm,  or  its  dimensions,  the  wheel  must  be 
marked  out  in  section  therefrom,  and  the  angles  of  the 
teeth  are  also  fixed  by  it,  as  follows:  There  are  three 


10:2 


PRACTICAL  PATTERN  MAKlXG. 


principal   dimensions   on   the   worm   (Fig.    181),   the   pitch 
diameter  p  (see  Figs.   182  and  183),  the  pitch  Q,  and  the 


Fig.  182.  Fig.  183. 

Figs.  182  and  183.— End  View  and  Section  of  Worm  Casting. 

tooth  section  s.  P  and  Q  together  govern  the  angle  of  the 
teeth  on  the  worm  wheel ;  P  governs  the  sectional  curves 
of  the  teeth,  Q  the  tooth  centres,  and  s  the  tooth  forms. 


Fig.  184.— Marking  Section  of  Worm  Wheel. 

It   may  be   noted   that  the   sections   of  the   worm  tooth 
should  always  be  those  shown — namely,   sloping  like  tho 


WORM  WHUEL  PATTERN. 


103 


rack  teeth  for  involute  wheels.     The  points  and  roots  are 
very  slightly  rounded,  only  just  to  avoid  sharp  angles. 

Fig.  184  shows  the  methods  of  using  the  worm  to  get 
the  leading  dimensions  of  the  wheel.  First  as  to  the 
section  of  the  wheel.  The  pitch  diameter  P  of  the  worm 


F.g.  186. 

Figs.  185  and  186.— Half -pattern  of  Worm  Wheel  Body  Glued  up 
Roughly. 

comes  in  contact  with  the  pitch  diameter  of  the  wheel  Q 
on  the  central  plane  A  A,  so  that  the  diameters  measured 
from  B  B  are  not  the  true  pitch  diameters,  but  are  larger, 
and  are  regulated  by  the  radius  of  the  worm.  The  sec- 
tional curves  of  the  wheel  teeth,  allowing  for  clearance, 


104  PRACTICAL  PATTERN  MAKING. 

are  struck  from  the  centre  of  the  worm,  as  shown,  and  the 
ends  of  the  teeth  radiate  from  the  centre.  The  thickness 
of  the  rirn  c,  equal  to  the  tooth  thickness,  is  added, 
and  the  curve  for  that  also  struck  from  the  centre  of  the 
worm.  The  angle  of  the  wheel  teeth  is  obtained  by  laying 
down  the  circumference  of  the  pitch  diameter  i>  of  the 
worm  and  the  pitch  Q,  as  the  two  sides  of  a  right-angled 
triangle,  and  the  hypotenuse  E  will  give  the  angle  of  the 
wheel  teeth.  It  is  necessary  to  get  this  angle,  as  a  guide 
by  which  to  glue  on  the  blocks  for  the  teeth,  even  though 
the  latter  are  shaped  with  the  worm  as  a  template.  If  the 
teeth  are  marked  off  and  shaped  directly  without  the  aid 
of  the  worm  as  a  template,  then  it  is  by  this  angle 
that  the  teeth  are  marked  round  at  definite  distances  out 
of  the  perpendicular  on  the  joint  face  A  A,  and  on  the  dia- 
meters B  B.  The  total  amount  of  departure  of  the  teeth 
from  the,  perpendicular  on  the  extreme  diameters  B  B  is 
equal  to  F,  obtained  by  the  angle  of  the  worm  wheel  teeth. 

The  method  of  lining  out  being  now  clear,  the  making 
of  the  pattern  involves  a  neat  bit  of  work.  Such  patterns 
must  always  be  glued  up  in  segments,  and  always  parted 
along  the  central  plane  A  A.  Readers  have  already  been 
told  the  methods  adopted  in  building  up  segmental  work  to 
ensure  permanence  of  form.  Figs.  185  and  186  show  one- 
half  the  pattern  built  up  roughly,  that  is,  not  turned  to 
shape,  the  method  being  suitable  for  a  wheel  of  about 
2  ft.  diameter,  or  more.  Far  smaller  wheels  fewer  seg- 
ments may  be  used,  and  the  plated  portion  can  be  solid 
instead  of  being  formed  in  two  thicknesses  as  shown.  The 
illustration  explains  itself. 

There  are  two  methods  of  jointing  the  halves,  shown  in 
Figs.  187  and  188.  In  the  first  the  plate  is  built  in  one, 
either  with  or  without  segments,  and  the  top  part  of  the 
pattern  is  jointed  as  a  ring  to  it.  This  is  not  so  durable  a 
method  as  the  one  shown  in  Fig.  188,  in  which  each  half 
ring  is  glued  to  half  the  plate  thickness.  The  loose  un- 
stayed  ring  in  Fig.  187  is  apt  to  go  out  of  truth  in  time  ; 
but  in  Fig.  188  both  rings  are  supported  alike  with  a  half 
thickness  of  plate. 

After  the  rings  are  glued  up,  the  curve  of  the  rim  upon 
which  the  teeth  are  to  bed  is  turned  by  template  A  (Fig. 
189)  made  from  the  drawing.  This  curve,  and  the  joint 


WORM  WHEEL  PATTERN, 


105 


faces  of  the  two  halves,  are  the  parts  to  be  turned  first, 
because  they  are  the  most  important.  Afterwards  the 
halves  can  be  re-chucked  by  the  central  stud  B  and 
corresponding  stud  hole,  and  the  edges,  the  inner  rim 
curves,  and  the  outer  faces  of  the  rim  turned.  In  addition 
to  the  central  stud,  it  is  necessary  to  insert  a  dowel 


Fig.  187. 


Fig.  188,  Fig.  189. 

Figs.  187  and  188.— Jointing  Worm  Wheel  Pattern.     Fig.  189.— 
Turning  Outside  of  Wheel  Rim  by  Template. 

between  the  two  halves  of  the  pattern  to  preserve  the 
two  halves  always  in  the  same  position  in  relation  to  each 
other,  so  that  the  edges  of  the  teeth  shall  always  coincide 
precisely. 

Before  ire-chucking,  the  blocks  for  the  teeth  ought  to  be 
fitted  and  glued  on,  otherwise  time  will  be  wasted.  The 
half-lengths  of  the  teeth,  with  turning  allowances,  are  fitted 


10(»  PRACTICAL  PATTERN  MAKING. 

with  a  chisel  at  approximate  angles  to  the  turned  seatings, 
which  are  chalked  to  show  points  of  contact.  They  will 
have  the  appearance  seen  in  Fig.  190.  They  are  then 
faced  and  turned  to  the  form  in  Fig.  191  with  template  A, 
after  which  the  re-chucking  before  alluded  to  will  follow 


Fig.  190.— Tooth  Block  Glned 
on  Wheel  Rim. 


Fig.  191.— Turning  Tooth  Points 
by  Template. 


Fig.  192. — Turning  Inside'of 
Wheel  Rim  by  Template. 


(Fig.  192).  Then  the  face  B  will  be  skimmed  over  to  tho 
required  thickness,  and  upon  it  a  template  A  will  be  set  for 
checking  the  turning  of  the  inside  of  the  rim  and  its  edges 
and  the  ends  of  the  teeth.  This  is  shown  clearly  by  the 
illustrations,  so  that  more  detailed  explanation  is  not 
required. 

The  centres  of  the  teeth  are  now  to  be  pitched 


WOEM  WHEEL  PATTERN. 


107 


the  joint  face  A  A  (Fig.  184)  on  one  half  of  the  pattern.  To 
obtain  the  forms  of  the  teeth,  see  Fig.  193  and  194.  For  all 
involute  teeth  there  is  a  base  circle  A  (Fig.  193),  as  well  as 
the  pitch  circle  B,  which  is  used  for  convenience.  The  base 
circles  of  a  pair  of  wheels  coincide  approximately  with  the 


Fig.  H>3.—  Forms  of  Teeth  on  Worm  and  Wheel. 

roots  and  the  points  of  the  teeth  c.  A  line  drawn  tangent 
to  both  base  circles  is  the  pitch  circle  or  path  of  con- 
tact of  the  teeth.  In  a  worm  tooth,  as  in  a  rack,  the 
tooth  flanks  are  at  right  angles  with  the  tangent  line 
(Fig.  193).  In  the  wheel  tooth  the  movement  of  the 
tangent  line  on  the  base  line  A  gives  the  curve  for  the 
flanks.  This  is  done  in  practice  by  laying  a  slip  of  wood 
carrying  a  needle-point  against  a  template,  cut  to  the 
radius  of  the  base  line,  and  moving  the  slip  around  it,  the 
needle-point  then  marking  the  tooth  curve  (Fig.  194).  The 


Fig.  194. — Template  for  Marking  Tooth  Curves. 

angle  of  obliquity  usually  adopted  for  rack  teeth  is  75° 
with  the  line  of  centres. 

The  teeth  should  all  be  marked  out  in  the  joint  face  of 
one  half  the  pattern,  and  cut  in  a  little  way  with  the 
chisel.  The  teeth  on  the  other  half  of  the  pattern  can 


108 


PRACTICAL  PATTERN  MAKING. 


be  marked  from  them,  and  cut  or  set  in.  That  is  all  the 
marking  out  that  is  really  necessary.  The  two  half  patterns 
are  screwed  together,  chalking  the  outlines  set  in,  to 
prevent  risk  of  cutting  into  the  tooth  forms  in  the  sub- 
sequent work.  Take  the  worm  and  place  it  truly  between 
centres  in  the  lathe.  Take  the  wheel,  and  mount  it  on  a 
pin  or  pivot  fixed  in  a  socket-rest  in  such  a  way  that  its 
central  plane  A  A  (Fig.  184)  will  coincide  with  the  central 
axis  of  the  worm,  the  wheel  being  perfectly  horizontal, 
and  so  arranged  that  it  will  move  round  on  the  pin  with 
freedom,  and  without  play.  The  worm  and  wheel  pattern 
will  then  occupy  precisely  the  same  relations  which  the 
castings  will  occupy  when  working.  The  only  difference 


Fig.  19.-J.— Cutting  Wheel  Teeth. 

will  be  that  the  T-  rest  socket  must  be  set  and  guided  by  a 
couple  of  parallel  strips  screwed  across  the  lathe-bed,  so 
that  it  can  be  slid  to  and  fro,  putting  the  wheel  into  and 
out  of  gear  with  the  worm.  Fig.  195  shows  a  suitable 
arrangement  in  plan,  A  A  being  the  lathe  bearers,  B  B 
parallel  strips,  and  c  the  T-rest  socket. 

It  is  now  easy  to  see  that  the  wheel  teeth  can  be  cut 
carefully  and  tested  until  they  make  a  perfect  gear  with 
the  worm.  When  cutting  the  teeth,  the  T-rest  socket  is 
drawn  back.  To  ascertain  the  amount  of  contact  and  accu- 
racy attained,  it  is  thrust  forward,  and  the  worm  is  re- 
volved by  hand,  carrying  the  \vheel  round  a  portion  of  a 
circle,  and  leaving  marks  of  contact  on  its  tooth  flanks,  the 
worm  being  smeared  with  red  lead  and  oil  for  the  purpose. 

If  the  rig-up  is  steady  and  due  care  is  taken  that  the 


WORM  WHEEL  PATTERN.  109 

tooth  forms  set  in  on  the  middle  plane  are  not  cut  below, 
there  is  no  need  to  mark  the  tooth  forms  on  the  outer 
faces  B  B  (Fig.  184).  Still,  it  is  safer  on  the  whole  to  do  so. 
After  working,  therefore,  three  or  four  teeth  carefully,  the 
forms  on  the  outer  faces  B  B  will  be  developed— differing, 
of  course,  from  those  on  the  joint  face  A  A  (Fig.  184) — and 
their  widths  and  the  location  of  the  radii  of  their  flanks 
can  then  be  taken  and  set  out  round  the  remainder  of  the 
wheel.  The  time  of  marking  out  is  not  wholly  lost,  be- 
cause, after  marking,  all  the  teeth  can  be  cut  in  by  the 
lines  nearly  to  shape  without  any  trial  in  the  worm  until 
the  final  corrections  are  necessary. 

If  these   directions  are  followed  carefully,   the   result 
will  be  a  more  perfect  gear  than  can  possibly  be  attained 


Fig.  190.— Cross  Section  of  Finished  Worm.  Wheel  Pattern. 

by  any  method  of  marking  out  direct  from  a  drawing  of 
the  tooth  forms.  The  conditions  being  precisely  those 
which  exist  in  actual  gear,  the  rest  is  a  matter  of  care  on 
the  part  of  the  workman. 

Fig.  196  shows  the  wheel  complete  in  cross  section,  with 
teeth,  central  stud,  dowel,  bosses,  and  prints  in  place. 
The  bosses  may  be  screwed  or  studded  on.  The  latter  is 
more  favourable  for  subsequent  alterations  in  bores,  if 
such  are  likely  to  be  required.  Fig.  196  shows  the  central 
web  built  up,  each  half  in  two  thicknesses,  as  in  Figs.  185 
and  186 ;  but  some  of  the  illustrations  show  one  thickness 
only  of  solid  stuff.  In  adopting  the  latter  method,  how- 
ever, it  is  always  best  to  make  open  joints,  if  a  wheel  is 
over  10  in.  or  12  in.  in  diameter.  The  segments  will  hold 
together  the  strips  which  form  the  plate. 


110 
CHAPTER  X. 

LATHE-BED  PATTERNS. 

THIS  chapter  will  describe  first  the  pattern  for  a  lathe- 
bed  (Figs.  197  and  198),  a  plain  bed  for  a  hand-turning 
lathe  without  slide-rest.  Fig.  199  is  a  cross  section. 
Dimensions  are  not  given,  and  are  not  necessary,  but  the 
figures  are  drawn  proportionately  for  any  lathe  of  from 
3-in.  to  7-in.  or  8-in.  centre,  and  the  method  here  described 
for  constructing  the  pattern  will  be  correct  for  any  lathe 
bed  of  that  type.  Its  parts  are,  sides  A,  sliding  ways  B, 
cross-bars  c,  mouldings  or  fillets  D,  and  feet  or  flanges  E. 
There  are  two  ways  in  which  the  pattern  for  such  a  bed 
may  be  made — first,  like  its  casting  with  some  very  slight 
x 

:  B       B 


v----^-f--r-r    B---  ----::::  --------  -----4--"  : 

3c     E|   ;   Oc                                        IE     c[ 

Ha 

Fig.  197. 
B 

E 
Fig.  J99. 

'                  1    v 

i  :  ii  o—                   i 

Fig.  198. 
Figs.  197  to  199.— Lathe-bed  Casting. 

differences ;  or  it  may  be  made  so  that  only  the  outer 
faces  correspond  with  the  form  of  the  casting,  and  the  in- 
terior portions  are  represented  by  core-prints  only,  core- 
boxes  being  required  in  this  case  for  coring  out.  The  first 
method  is  much  preferable  in  the  case  of  the  bed  in 
question. 

In  moulding  any  lathe-bed,  it  must  be  remembered  that 
the  sliding  faces  must  be  cast  downwards  with  the  object 
of  securing  clean  metal  there.  So  this  settles  the  way  in 
which  the  pattern  shall  be  tapered  and  which  portions  are 
to  be  kept  loose. 


o  111 


112  PRACTICAL  PATTERN  MAKING. 

Figs.  200  and  201  show  the  pattern  of  the  bed  in  eleva- 
tion and  cross  section,  just  as  it  is  laid  down  during  the 
operation  of  moulding.  It  is  well  when  making  a  pattern 
always  to  picture  it  mentally  just  as  it  stands  when 
being  moulded,  and  the  details  then  seem  to  work  out 
naturally.  The  sides  A  are  tapered  downwards,  say  from 
•J-y  in.  to  3^-  in.  in  beds  of  from  4  in.  to  6  in.  deep,  and  an 
much  as  £  in.  in  deeper  beds,  say  from  7  in.  to  8  in.  deep  ; 
that  is,  they  are  thinner  by  that  amount  at  the  bottom 
than  at  the  top  edges,  as  shown  in  the  cross  section  to  the 
left  hand.  The  cross-bars  c  are  tapered  similarly. 

When  putting  together  the  sides  and  cross-bars  ;of 
such  a  pattern  as  this  two  difficulties  are  likely  to  be 
encountered.  One  is  that  of  getting  the  pattern  quite 
straight  lengthwise,  the  other  that  of  keeping  it  out 
of  winding.  The  first  is  due  to  the  stuff  being  planed 
crooked,  the  second  to  its  being  planed  winding,  or  to  the 
ends  of  the  cross-bars  not  being  planed  to  precisely  the 
same  bevels,  and  also  to  the  cross-bars  not  being  inserted 
precisely  alike,  as  regards  position  up  or  down.  If  the 
pattern  is  winding  when  finished  there  is  no  means  of 
getting  the  winding  out  afterwards.  It  must  be  pulled 
apart  and  corrected,  or  the  casting  will  be  winding. 

To  prevent  such  inaccuracy,  the  sides  must  be  planed 
truly  first,  straight  lengthwise,  and  free  from  winding.  In 
thin  stuff  like  this,  which  will  not  be  more  than  \  in.  or  f  in. 
thick  in  any  case,  it  is  not  easily  done.  Jack  plane  the  stuff 
all  over  first,  removing  the  outside  and  exposing  the  grain 
to  the  air  ;  let  the  job  stand  for  a  day  or  two  and  then 
finish  with  the  trying  plane,  using  a  straight-edge  for 
checking  the  truth  lengthwise,  and  winding  strips  for  the 
twist  or  winding  of  the  stuff.  If  the  face  of  the  work  is 
true,  the  strips  when  looked  across  will  show  a  perfectly 
level  plane,  no  portion  of  the  edges  standing  any  higher 
than  the  rest. 

The  cross-bars  c  should  be  planed  preferably  with  the 
grain  running  across  as  shown,  then  any  shrinkage  which 
may  occur  will  not  affect  the  width  of  the  lathe-bed  as  it 
would  if  the  grain  ran  perpendicularly ;  also  the  pattern  is 
stiffer  than  it  would  be  if  the  grain  ran  perpendicularly. 
To  ensure  symmetry  and  prevent  risk  of  winding,  the  ends 
of  the  bars  should  be  planed  tapered  from  a  centre  line, 


LATHE-BED  PATTERNS.  113 

as  in  Fig.  202,  the  dimensions  F.  being  equal,  and  G  also 
equal,  the  difference  between  F  and  G  being  exactly  the 
same  as  that  due  to  the  taper  on  the  inner  faces  of  the 
sides  A.  Then  having  one  cross-bar  planed  correctly,  mark 
the  others  from  it  with  a  scriber,  and  plane  accurately 
to  the  scribed  lines.  Then  if  the  cross-bars  are  all  screwed 
between  the  sides  with  their  edges  o  exactly  level  with  the 
edges  of  the  sides  A,  there  will  be  no  risk  of  winding 
occurring. 

The  sides  are  screwed  to  the  cross-bars,  and  need  not 
be  removed  during  moulding.  The  top  strips  B,  however, 
must  not  be  fastened,  yet  they  have  to  be  secured  in  place 
during  ramming  up  of  the  pattern.  This  is  done  by 
the  use  of  dowels  F  (Figs.  200  and*  201),  which  retain  the 
strips  in  place,  but  which  permit  of  the  taking  away  of  the 
main  body  of  the  pattern  from  the  strips  after  the  mould- 
ing is  completed.  The  mould  is  jointed  along  the  plane 
G  and  then,  after  the  removal  of  that  portion  of  the  mould 
which  contains  the  main  body  of  the  bed,  the  strips  B  are 
left  exposed  in  the  bottom  part  to  be  withdrawn  from  the 
sand  separately. 

On  these  strips  an  allowance  for  planing  the  casting  has 
to  be  made.  The  allowance  need  not  exceed  J  in.  on  each 
planed  face  unless  the  bed  is  exceptionally  long,  or  unless 
the  foundry  where  it  is  made  turns  out  rough  castings, 
and  then  ^  in.  will  not  be  too  much.  The  faces  to  be 
planed  are  the  top  H  (Fig.  200)  for  the  poppet,  etc.,  to  slide 
upon  ;  the  inner  face  J  for  the  headstock  and  poppet  to  fit 
between ;  and  the  outer  edge  K  for  good  appearance. 
These  strips  must  be  dowelled  accurately  upon  the  sides. 
If  they  do  not  lie  parallel  and  in  winding  with  one  another 
some  of  the  planing  allowances  will  have  to  be  used  in 
getting  the  casting  t  rue,  and  if  the  inaccuracy  amounts  to 
much  it  may  happen  that  the  casting  will  not  hold  up  to 
desired  dimensions. 

The  strips  being  dowelled  on  very  narrow  edges  will 
not  lie  very  steadily  on  them,  but  that  will  not  matter ;  if 
put  on  truly,  they  will  be  all  right  and  steady  when  laid 
upon  the  levelled  bed  of  sand  upon  which  the  pattern  will 
be  moulded. 

The  filleting  D  is  prepared  in  separate  strips ;  it  is 
screwed,  and  it  may  also  be  glued,  along  the  sides.  These 


Ill 


PRACTICAL  PATTERN  MAKING. 


^      <  (tim 


•*  4 

-    U< 


LATHE. BED  PATTERNS.  115 

strips  act  as  material  stiffeners  to  the  pattern,  as  they 
also  do  to  the  casting. 

The  feet  E  by  which  the  bed  is  bolted  to  its  standards, 
may  either  be  screwed  on  or  dowelled  on,  it  matters  little 
which.  They  are  shouldered  to  fit  within  the  sides  A. 
Their  faces  may  be  planed  all  over,  or  narrow  strips  may 
be  used  as  shown.  Fig  203  shows  the  under  side  of  one  of 
these  pattern  feet.  The  strips  will  save  some  labour  if  the 
lathe  builder  prefers  to  chip  instead  of  planing. 

It  will  facilitate  the  moulder's  work  if  the  pattern  is 
well  glasspapered  across  the  grain,  along  the  width  of  the 
stuff,  and  on  the  sides  and  ribs,  using  a  rubber  for  the 
purpose.  This  will  remove  the  plane  marks  and  make  a 
nice  smooth  surface  favourable  to  delivery.  When  the 
pattern  delivers  freely  from  the  mould,  there  is  tolerable 
certainty  that  the  casting  will  be  just  like  the  pattern  ;  but 
when  the  moulder  has  to  mend  up,  elements  of  uncertainty 
and  inaccuracy  come  in.  Two  applications  of  clear  shellac 
varnish  will  suffice,  each  being  rubbed  down  when  dry  with 
fine  glasspaper. 

In  reference  to  shrinkage  allowances,  these  may  almost 
be  neglected  in  small  beds.  If  the  bed  is  4  ft.  long  the 
difference  in  length  due  to  shrinkage  will  be  about  |  in.  ; 
if  the  bed  is  5  in.  wide  over  the  strips  the  shrinkage  in 
breadth  will  only  be  in  theory  a  full  -^  in.,  and  will  prob- 
ably amount  to  nothing  at  all,  because  the  moulder  will 
rap  the  pattern  to  that  extent. 

The  making  of  a  pattern  for  a  gap  lathe-bed  is  different 
from  that  just  described  for  a  plain  bed  which  was  made 
to  deliver  without  cores.  The  one  shown  by  Figs.  204  to 
206  will  be  better  if  cored  out,  because  the  cutting  out 
of  the  gap  would  render  a  pattern  for  self-delivery  very 
flimsy.  That  such  is  the  case  is  evident  from  a  glance  at 
Figs.  204  and  205,  where  it  is  seen  that  the  cutting  out  of 
the  gap  would  break  the  continuity  of  the  wood  in  the  side 
webs  A,  and  there  is  nothing  to  reinforce  their  rigidity. 
The  pattern  would  therefore  twist,  especially  in  small  beds 
of  light  scantlings,  say  with  sides  A  only  £  in.  or  f  in. 
thick.  The  pattern  is  also  rather  too  deep  at  the  gap  for 
easy  delivery.  Likewise,  in  many  instances,  as  in  Figs. 
204  to  206,  the  bottom  of  the  gap  is  bridged  over  with 
metal,  and  that  necessitates  an  awkward  lift  of  sand  in 


116 


PRACTICAL  PATTERN  MAKING. 


LATHE-8ED  PATTERNS.  117 

the  top  N  above  the  bridged  part— that  is,  "  top  "  as  the 
pattern  moulds.  Then  there  are  deep  lifts  at  o  adjacent, 
which  would  require  a  good  deal  of  taper  in  the  pattern 
there. 

Another  good  reason  for  coring  such  beds  in  a  machine* 
maker's  shop  is  that,  as  lathe-beds  for  poppets  of  similar 
centres  often  have  to  be  supplied  of  different  lengths  to 
suit  customers,  it  is  easier  to  alter  the  length  of  a  solid 
pattern  provided  with  core-prints  and  core-boxes,  than 
one  made  to  deliver  itself  without  coring. 

There  is  little  more  difficulty  in  this  job  than  in  the 
last,  but  there  is  more  work  involved.  The  type  of  bed 
and  proportions  shown  in  the  illustrations  would  be  suit- 
able for  a  lathe  of  from  3^  in.  to  7  in.  centre. 

In  Figs.  204  to  206  A  shows  the  sides ;  B,  the  bearers ; 
c,  the  cross-bars ;  D,  the  gap  ;  E,  the  feet ;  F,  facings  for 
the  brackets  for  the  leading  screw ;  G  H,  fillets. 

The  main  body  of  the  pattern  is  made,  not  from  solid 
stuff,  but  by  "boxing  up,"  by  which  the  pattern  is  pre- 
vented from  warping  to  any  important  extent.  Boxing  up 
occupies  more  time  than  cutting  from  solid  stuff,  but  it 
saves  timber,  and  produces  a  better  job.  The  method  oi 
boxing  up  is  shown  in  Figs.  207  to  211,  the  pattern  being 
drawn  in  those  figures  in  the  position  which  it  occupies 
during  moulding — that  is,  upside  down.  Fig.  207  is  a 
cross  section  through  the  main  body  of  the  pattern, 
showing  the  method  of  building  up  ;  Fig.  208  is  a  longi- 
tudinal elevation  ;  Figs.  209  its  plan,  looking  down  on  the 
bearers  ;  Fig.  210,  the  plan  of  its  under  side ;  Fig.  211,  a 
longitudinal  section  to  show  the  cross-bars. 

The  rectangular  section  is  built  up  of  two  vertical 
sides  A,  A,  running  the  entire  depth  (Figs.  207  to  209),  in- 
cluding the  thickness  due  to  the  undercut  bearers  B,  B,  plus 
£  in.  for  planing,  and  cut  to  the  vertical  outline  of  the  bed 
(Fig.  208).  Between  these  and  the  top  and  bottom  por- 
tions c,  D,  which  complete  the  rectangle,  cross-bars  E  are 
fastened  by  nailing  or  screwing.  At  the  curved  portions 
F  (Figs.  210  and  211),  blocking  is  inserted,  sufficiently  thick 
to  permit  of  the  cutting  out  of  the  curves.  The  sides  A,  A, 
and  the  ends  of  the  pattern  are  tapered,  the  amount  vary- 
ing with  the  depth  of  bed — say,  from  3\  in.  to  ^  in.  on 
each.  If  the  gap  has  a  solid  bottom,  as  in  Figs.  204  and 


118 


PRACTICAL  PATTERN  MAKING. 

i 


LATHE-BED  PATTERNS.  119 

205,  it  may  be  either  cored  out  or  cut  out  in  the  pattern. 
The  work  will  be  lessened  and  the  pattern  strengthened 
by  coring  it  out.  If  the  gap  goes  right  through — that  is, 
without  a  solid  bottom. — it  will  be  cored  out.  It  is  here 
assumed  that  it  will  be  cored  out. 

On  the  outer  faces  of  the  pattern,  those  portions  of 
the  bearer  B  with  the  strips  which  stand  beyond  the  faces, 
will  be  skewered  on  (Figs.  207,  208,  209,  and  210),  or 
else  fitted  with  easy-fitting  dovetails  (Fig.  212).  The 
skewers  are  just  as  good  as  dovetails,  and  do  not  occupy 
so  much  time  in  fitting.  Dovetails  are  neater,  and  if  well 
fitted  are  very  good.  They  are  adopted  in  good  work  to 
prevent  risk  of  the  loose  pieces  becoming  shifted  out  of 
place  in  the  mould.  Note  that  extra  allowances  for 
planing  the  castings  will  have  to  be  made  all  over  the  sur- 
faces of  these  bearers  ;  from  J  in.  to  ^  in.  is  usually  given. 

For   coring  out  the   interior,    narrow   prints     G   (Figs. 


Fig.  212— Fitting  Baarers  with  Dovetails. 

207,  208,  and  209)  are  nailed  or  screwed  along  the  centre 
of  the  pattern.  They  will  be  of  the  same  width  as  the 
tenons  on  the  under  side  of  the  heads,  minus  the  planing 
allowances  between  the  bearers.  Thus,  if  the  space  be- 
tween the  bearers  is  2  in.  in  the  finished  casting,  the  print 
G  will  be  If  in.  wide.  From  \  in.  to  f  in.  thick  will  be  suit- 
able for  these  prints.  H  (Figs.  208  and  209)  is  the  print  for 
the  gap-core.  It  is  made  of  the  same  width  over  as  the 
sides  A,  A  (Figs.  204  and  205).  This  leaves  the  fillets  K 
around  the  gap  standing  beyond  the  print.  If  the  print 
comes  out  to  the  faces  of  the  fillets,  the  core  could  not.be 
got  in  unless  the  sides  of  the  mould  were  taken  away.  At 
I  (Figs.  208  and  210)  is  shown  the  print  for  coring  out  the 
metal  underneath  the  gap. 

The  fillets  J  (Figs.  207,  208,  and  210),  shown  at  G  in 
Figs.  204  and  205,  go  round  the  lower  edges  of  the  ribs  A, 
stiffening  them,  and  will  be  fastened  on  permanently  with 
nails  or  screws.  The  method  of  their  fitting  is  indicated  by 
the  timber  shading.  The  fillet  K  in  Fig.  208,  which  runs 


120 


PRACTICAL  PATTERN  MAKING. 


round  the  gap,  corresponding  with  H  in  Figs.  204  and  205,  is 
skewered  on  loosely.     If  these  fillets  were  .fastened  per- 


FJ>.  213. 


Fig.  214. 
Figs.  213  and  214.— Core-box  for  Taking  out  Portion  of  Gap  Lathe-bed. 

manently  they  would  prevent  the  withdrawal  of  the  pat- 
tern from  the  mould. 


Fig.  2 1C. 


Fig.  217. 
Figs.  215  to  217.— Core-box  for  Taking  out  Portion  of  Gap  Lathe-bed. 

The  feet  E  (Figs.  204  to  206),  which  receive  the  stand- 
ards, are  fitted  differently  from  those  illustrated  in  Fig. 
201,  p.  111.  In  the  present  case  part  of  their  thickness, 


LATHE-BED  PATTERNS. 


121 


L  L  (Figs.  208  and  210),  is  nailed  on  the  pattern.  The  re- 
mainder, or  supplementary  portion,  which  comes  within 
the  bed,  seen  dotted  in  Figs.  204  and  205,  will  go  in  the 
core-boxes.  The  facings  F  (Figs.  204  to  206)  for  the 
brackets  which  carry  the  leading  screw  are  nailed  on  per- 
manently at  M  (Figs.  208  and  210).  These  complete  the 
pattern  for  a  gap  lathe-bed ;  but  the  core-boxes  have  now 
to  be  made. 

It  is  obvious  that  the  cross-section  inside  of  the  core- 
boxes   must   be   the   same   as  that   of   the   inside   of  the 


Fi?.  218. 


Fig.  21 9. 
Figs.  218  and  219.— Core-box  for  Taking  out  Portion  of  Gap  Lathe-bed. 

bed  casting,  and  that  their  outlines  and  dimensions  length- 
wise must  correspond  with  the  outlines  of  the  bed,  and 
also  that  of  certain  dimensions  measured  lengthwise. 
These  core-boxes  are  shown  in  Figs.  213  to  223,  with 
dimension  reference  letters  corresponding  with  similar 
lettering  on  the  casting  (Figs.  204  to  206)  and  pattern 
(Figs.  207  to  210).  They  are  drawn  in  the  positions  in 
which  the  cores  are  rammed  and  placed  in  the  mould — 
that  is,  upside  down. 

Figs.  213  and  214  show  the  core-box  for  coring  out  the 
portion  p  of  the  bed  (Figs.  204  to  206) ;  Figs.  215  to  217 


122 


PRACTICAL  PATTERN  MAKING. 


that  for  coring  out  Q ;  Figs.  218  and  219,  that  for  K ;  Figs. 
220  and  221,  for  the  gap  D  ;  Figs.  222  and  223,  for  the  recess 
N.  A  cross-section  of  one  main  bed-box  is  shown  at  the 
left-hand  of  Figs.  215  to  217.  That  is  also  correct  for  Figs. 
218  and  219,  and  the  lower  portion  of  it  also  for  Figs.  213 
and  214. 

Taking  the  sectional  dimensions  of  the  main  boxes  first : 
the  .distances  s  (Figs.  213  to  219)  correspond  with  the  dis- 
tance s  between  the  ribs  A  (Figs.  204  to  206),  the  distance 
T  with  the  distance  w  between  the  bearers  B,  B  in  Figs.  204 
to  206,  minus  the  planing  allowances,  the  actual  distance 


:     Fig:.  220. 


1<V.  221. 


Figs.  220  and  221.— Core-box  for  Coring  out  Portion  of  Gap  Lathe-bed. 

corresponding  with  the  width  T  of  the  prints  G,  in  Fig. 
207.  The  total  depth  of  the  boxes  will  equal  the  total 
depth  of  the  bed  pattern,  plus  the  planing  allowance  on 
the  faces  of  the  bearers  B,  B,  plus  the  thickness  of  the 
prints  G.  The  thickness  of  the  internal  bearer  strips 
equals  the  thickness  u  of  the  bearers  B,  B  (Figs.  204  to 
206),  plus  their  planing  allowance  on  their  top  and  unde£ 
faces,  plus  the  thickness  of  the  prints  G  (Fig.  207).  The 
curved  outlines  of  the  boxes  (Figs.  215  to  219)  corit.- 
spond  with  the  curved  outlines  of  the  pattern  of  the  bed 
below  the  gap  (Figs.  204  to  208). 

The  cross  ribs  c,  in  the  casting  (Figs.  204  to  206),  are 
seerf  formed  in  the  core-boxes  (Figs.  213  to  219)  at  v,  and 


LATHE-BED  PATTERNS. 


123 


the  positions  of  these  ribs  in  the  casting  determine  the 
lengths  of  the  boxes ;  each  core  ends  against  the  face 
of  a  rib.  They  could  also  be  made  to  end  over  the 
centre  of  a  rib.  Or  alternatively  the  entire  interior  of 
the  casting  could  be  taken  out  with  a  single  core,  but 
there  are  objections  to  this.  The  method  shown  in  Figs. 
213  to  223  is  the  most  suitable.  In  Figs.  213  to  219,  the 
lengths  Y,  z,  z'  of  the  boxes  respectively  coincide  in  each 
case  with  the  lengths  y,  z,  z'  shown  in  the  casting  (Figs. 
204  to  206).  The  box  (Figs.  213  and  214)  includes  two 
cross-ribs ;  Figs.  215  to  217,  one ;  Figs.  218  and  219,  two. 
In  the  boxes  (Figs.  213,  214,  218,  and  219)  facing  pieces 


^       Fig.  222. 


Fig.  223. 


Figs.  222  and  223.— Core-box  for  Taking  out  Portion  of  Gap  Lathe-bed. 

w  are  seen  inserted  next  the  ends.  These  form  the  sup- 
plementary thicknesses  of  the  facings  E  cast  on  the  bot- 
tom of  the  bed  (Figs.  204  to  200),  the  remaining  portions 
of  which,  L,  are  put  on  the  pattern  (Figs.  208  and  210). 

In  Figs.  213  to  219  each  core-box  is  shown  made  as  a 
distinct  and  separate  box.  They  would  not  be  made  thus 
in  the  pattern-shop,  unless  a  good  many  lathe  beds  were 
wanted  all  alike.  If  only  two  or  three  beds  were  re- 
quired one  core-box  would  be  made  to  do  duty  for  Figs.  215 
to  219,  then  after  one  core  has  been  made  for  Figs.  215  to 
217,  the  necessary  alterations  in  length  and  in  regard  to 
the  supplementary  facing-piece  and  cross-rib  would  be 
made  to  adapt  the  box  for  Figs.  218  and  219. 

The  box  (Figs.  220  and  221)  is  for  coring-out  the  gap, 
the  core  dropping  into  the  impression  of  the  print  H  (Figs. 


124  PRACTICAL  PATTERN  MAKING. 

208  and  209).  The  length  Y'  corresponds  with  the  length 
of  the  gap,  x'  with  the  width  over  the  ribs  A  in  Figs.  204 
to  206,  w'  with  the  depth  plus  the  print  thickness  which 
stands  above  the  bearers  (Fig.  208).  The  convex  edges  at 
v'  (Figs.  213  and  214)  form  the  radius  at  the  bottom  of  the 
gap- 
Figs.  222  and  223  show  the  box  lor  coring  out  the  metal 
underneath  the  gap.  Its  length  u'  coincides  with  the 
length  of  the  print  I  (Figs.  208  and  210),  its  width  T'  with 
the  width  of  the  print,  and  its  depth  s'  with  the  depth  of 
the  recess,  plus  the  print  thickness. 

The  method  of  construction  of  the  core-boxes  is  ren- 
dered clear  by  the  drawings  ;  grooved  sides  and  ends  form 
the  framework  within  which  the  bearing-strips  and  cross- 
ribs  are  fitted.  The  sides  are  screwed  to  the  ends,  so  that 
when  the  cores  are  rammed  the  screws  can  be  removed 
and  the  sides  and  ends  drawn  away  from  the  cores.  For 
this  reason  it  is  not  necessary  to  taper  the  interior  of  the 
boxes  at  all.  The  shading  renders  the  disposition  of  the 
timber  apparent. 

A  pattern  and  core-boxes  constructed  according  to  these 
directions  will  not  give  trouble  to  the  moulder,  and  the 
casting  will  come  out  accurate. 


125 
CHAPTER  XI. 

HEADSTOCK  AND  POPPET  PATTERNS. 

PATTERNS  for  fast  headstocks,  suitable  for  small  lathes  of 
types  operated  by  treadle  or  by  power,  will  be  described 
first  in  this  chapter.  There  is  no  need  to  give  any 
dimensions,  or  to  show  the  castings  as  distinct  from  their 
patterns.  Three  types  will  be  illustrated,  the  forms  and 
proportions  o.f  which  will  be  adapted  for  all  lathes  suitable 
for  light  turning,  for  centres  ranging  from  3  in.  up  to  6  in. 
or  7  in. 

Figs.  224  to  226  illustrate  a  pattern  for  a  headstock  with 
back-gear,  suitable  for  hand-  or  for  slide-rest  turning,  and 
intended  to  take  hardened  steel  cone  collars  for  the 
mandrel.  There  are  three  ways  in  which  this  could  be 
moulded.  One  is  upside  down,  the  collar  bosses  being  in 
the  bottom  of  the  mould  and  the  flat  foot  in  the  top.  Then 
the  sand  above  the  projecting  lugs  c  would  have  to  be 
carried  on  drawback  plates,  and  this  is  not  desirable  for 
small  headstocks.  The  second  way  is  to  make  the  pattern 
solid,  and  to  mould  upon  its  side,  with  the  back-gear  bear- 
ings c  in  the  bottom.  This  necessitates  a  moulder's 
awkward  down-joint,  running  coincidently  with  the  curved 
edge  in  the  top  half,  down  as  far  as  the  centre  plane  of  the 
head,  and  this  method  is  not  recommended.  The  third  and 
also  the  best  way  is  to  joint  the  mould  exactly  along 
the  central  plane  H  H  of  the  pattern,  having  one  half  then 
altogether  in  the  top,  and  one  half  altogether  in  the  bottom. 
To  facilitate  this  method  of  moulding,  it  is  desirable, 
though  not  absolutely  necessary,  to  joint  and  dowel  the 
pattern  in  the  same  plane  H  H,  and  this  is  the  way  in  which 
the  figures  show  it  to  be  done.  Then  the  only  portions  which 
have  to  be  left  loose  from  the  main  body  of  the  pattern 
are  the  bosses  I  i  for  the  back-gear,  and  these  are  re- 
tained in  correct  position  during  ramming  by  means  of  a 
central  skewer  thrust  through  them  to  the  pattern  body. 

The  strongest  method  of  construction  is  indicated  in 
Figs.  224  to  226.  The  base  A  planed  up  in  two  widths  and 


126  PRACTICAL  PATTERN  MAKING. 

dowelled,  receives  the  two  uprights  B,  each  also,  of  course, 
in  two  widths.  The  base  is  rebated  to  take  the  uprights, 
or  the  uprights  may  be  dovetailed  into  the  base.  The 
horns  or  bearing  portions  c  for  the  back-gear  tenoned  into 
the  uprights  B  are  shown  as  separate  pieces.  This  is  to 
prevent  the  possible  warping  or  shrinkage  of  those  por- 


Figs.  224  to  22(5.— Back-geared 
Headstock  Tattern. 


Fig.  226. 

tions  of  the  pattern  out  of  truth,  which  might  happen  if 
the  horns  were  cut  from  the  solid  with  the  uprights.  After 
the  rebating  is  done,  and  the  uprights  cut  to  their  outlines, 
they  are  glued  and  screwed  to  the  base.  It  is  better  then 
to  glue  in  the  hollows  D  as  square  blocks,  after  the  glue  is 
dry,  and  then  to  plane  the  hollow  portions,  than  to  plane 
them  before  insertion.  The  pieces  E  used  for  the  setting  of 


HEAD8TOGK  AND  POPPET  PATTERNS.         127 

the  headstock  on  the  bearers,  may  be  tenoned  into  the  feet 
as  shown.  The  bosses  J  which  have  to  be  bored  for  the 
collars,  are  turned  in  halves  and  nailed  on  the  uprights ;  so 
also  is  the  boss  K  for  the  holding-down  bolts.  Bosses  to  be 
cut  in  halves  should  not  be  turned  solid  and  sawn  through 
the  middle — at  least  not  in  the  best  work,  though  it  is  often 
done  for  rough  patterns.  They  should  be  planed  to  make 
a  joint  previous  to  being  turned,  and  then  fastened  to  the 
face-plate  with  the  joint  in  the  centre,  and  so  turned.  The 
bosses  i  i  are  solid  and  loose. 

The  holes  are  not  shown  cored  as  it  is  better  not  to  core 
holes  in  small  headstocks  because  castings  are  frequently 
unsound  and  spongy  near  to  cored  holes ;  and  if  holes 


Fig.  228.— Curved  Horn  for 
Mandrel  Bearings. 


Fig.  227.— Bound  Parallel 
Prints. 

are  cast  out  of  centre  they  give  much  more  trouble 
in  boring  than  if  boring  is  done  out  of  the  solid.  In  no 
case  should  the  holes  be  cored  in  the  back-gear  bosses, 
that  being  a  troublesome  job,  involving  the  use  of  deep 
drop  prints.  If  holes  are  cored  for  the  main  mandrel  col- 
lars, then  plain  round  parallel  prints  must  be  put  on  in  the 
manner  indicated  at  Fig.  227.  But  even  then  the  cored 
holes  should  give  ample  margin  for  boring  say  f  in.  in 
diameter. 

The  horns  for  the  back-gear  mandrel  bearings  are 
shown  running  parallel  outwards,  but  they  are  often 
curved  as  shown  in  Fig.  228.  In  that  case  the  portions 
of  the  boss  that  stand  out  beyond  the  width  of  the 
narrowest  part  of  the  neck  must  be  skewered  on  loosely 


128 


PRACTICAL  PATTERN  MAKING. 


as   shown,   to  be   drawn   back   into  the  mould   after  the 
removal  of  the  main  body  of  the  pattern. 

The  headstock  pattern  shown  in  Figs.  229  to  231  is  of 
a  type  much  used  for  small  hand-lathes  with  gut-driven 
pulleys.  The  method  of  putting  the  parts  of  the  pattern 
together  is  similar  to  that  shown  in  the  previous  example, 
but  this  has  been  drawn  to  show  how  such  a  pattern 
should  be  made  if  unjointed.  It  would  be  preferable  to 
joint  and  dowel  it  like  the  last,  but  many  small  patterns 


Fig.  230. 


Figs.  229  to  231.— Small  Head- 
stock  Pattern. 


Fig.  231. 


are  made  solid.  The  pattern  will  mould  on  its  side,  and 
the  moulder's  sand-joint  will  run  from  H  to  I  round  the 
upper  curved  edges  of  the  uprights.  Then  it  will  be 
necessary  to  skewer  on  loosely  the  bosses  J,  the  boss  K, 
and  the  guides  L,  in  the  manner  shown.  The  timber 
shading  indicates  the  various  pieces  used  and  the  best 
direction  of  the  grain. 

Figs.  232  to  234  show  another  head  suitable  for  a  hand- 
turning  lathe,  but  made  for  divided  brass  bearings  in  the 
front  instead  of  for  steel  cones.  The  pattern  must  be 
jointed  along  the  centre,  H  H.  The  seating  for  the 


HEADSTOCK  AND  POPPET  PATTERNS.         129 

brasses  is  cored  out,  the  prints  being  shown  at  I,  a 
plain  square  core-box,  shown  in  Figs.  235  and  236,  being 
made  to  correspond.  The  uprights  are  shown  not  rebated 


.  232. 


Fig.  234. 


Figs.  232  to  234.— Small  Headstock  Pattern  with  Split  Bearing. 

into  the  foot,  but  simply  butted  to  it.  This  is  good 
enough  in  small  patterns,  because  the  gluing-in  of  the 
hollows  serves  to  keep  the  uprights  from  becoming 
knocked  out  of  place  during  moulding.  In  Figs.  232  to 


Fig.  23r. 


Fig.  236. 
Figs.  235  and  236. — Plain  Square  Core-box. 

234,  as  in  the  former  ones,  each  separate  piece  is  indicated 
by  its  appropriate  sectioning, 

The  taper  on  these  patterns  is  so  slight  that  it  may  be 
almost  neglected.    If  the  pattern  parts  are  made  thinner 


130 


PRACTICAL  PATTERN  MAKING. 


by  the  difference  of  two  or  three  shavings  only  on  the 
sides  which  are  lowermost  in  the  mould  than  on  the 
higher  sides,  that  will  be  sufficient  to  afford  ready  delivery. 
The  fast  heads  of  lathes  having  been  described,  atten- 
tion will  be  directed  to  the  construction  of  patterns  for 
the  loose  or  poppet  heads,  three  types  of  which  will  be 
discussed.  Each  one  is  suitably  proportioned  for  the 
smaller  size  of  lathes,  of  from  3-in.  to  6-in.  or  7-in. 
centres.  The  first  (Figs.  237  to  243)  is  of  the  type  used 


Fig.  239. 
Figsi.  237  to  239.— Heavy  Lathe  Poppet  Pattern. 

for  the  larger  class  of  lathes  ;  the  second  (Figs.  244  to 
246)  is  more  often  made  for  small  lathes  ;  while  the  third 
(Figs.  247  to  249)  is  of  a  rather  simpler  type,  formerly  used 
more  than  at  present,  the  poppet  consisting  of  a  pointed 
screw  only  instead  of  a  cylinder. 

The  poppet-heads  shown  in  Figs.  237  to-  243  may  be 
moulded  in  one  of  three  ways.  The  pattern  may  be  made 
solid  and  moulded  sideways ;  the  only  pieces  which  would 
'then  have  to  be  left  loose  are  the  hold-down  boss  i>  and  the 
guides  E,  and  these  would  have  to  be  skewered  ori.  The 


HEADSTOCK  AND  POPPET  PATTERNS, 


131 


objection. to  this  pattern  is  the  awkward  down-jointing  and 
lifting  where  the  barrel  is  united  to  the  vertical  webs  B. 

Another  way  is  to  make  the  barrel  loose  from  the  rest 
of  the  pattern,  the  pattern  then  moulding  as  shown  at 
Figs.  240  and  241,  in  which  figures  the  barrel  is  shown 


Fig.  240. 


Fig.  241. 


Figs.  240  and  241.— Moulding  Barrel  for  Lathe  Poppet,     Fig.  242.— 
Barrel  for  Lathe  Poppet,  with  Dowels  and  Hollows. 

away  from  the  uprights,  in  order  to  indicate  h'ow  the  two 
portions  of  the  pattern  are  fitted  and  dowelled.  Of  course, 
in  that  case  the  small  fillet  seen  in  Fig.  237,  where  the 
vertical  ribs  B  meet  the  barrel,  must  not  be  attached  to 
the  verticals,  or  they  would  prevent  the  withdrawal  of 
the  pattern  from  the  sand.  If  introduced  in  the  pattern 
at  all  they  must  be  fitted  round  the  barrel  as  shown  in 
Fig.  242.  They  may  be  let  in  grooves  as  shown,  or  fitted 
round  with  a  gouge,  and  glued,  or  flexible  hollows  may  be 
fitted  round.  But  it  is  not  necessary  to  fit  small  hollows 
like  these  to  the  smaller  class  of  patterns,  because  the 
moulder  will  sleek  the  angles  if  told  to  do  so.  For 


Fig.  243.— Turning  Poppet  Barrel. 

standard  repetition  work  they  should,  however,  be  aiways 
inserted.  This  is  a  very  good  and  common  way  of  making 
these  patterns,  and  it  ensures  sound  metal  about  the 
barrel,  where  it  is  most  wanted.  It  is  the  method 
illustrated  in  Figs.  237  to  239. 


132 


PRACTICAL  PATTERN  MAKING. 


Another  method  equally  good  is  to  joint  the  pattern 
along  the  central  plane  F  F  (Fig.  238).  Then  no  part  is  left 
loose,  and  everything  is  in  favour  of  easy  moulding.  The 
foot  A  will  be  prepared  first  in  two  pieces,  jointed  and 
dowelled  along  the  plane  F  F,  and  the  uprights  B  B  will  be 
either  rebated  into  it,  as  shown,  or  made  to  abut  simply, 
then  glued  and  screwed.  The  hollows  G  are  also  glued  in. 
The  barrel  is  turned  with  its  prints  H,  the  prints  being 
made  parallel.  The  barrel  is  in  halves,  and  is  jointed 
and  dowelled  and  secured  for  turning— not  turned  first  and 


Fig.  240. 
Figs.  242  to  246.— Well-designed  Lathe  Poppet  Pattern. 

sawn  through  afterwards.  In  a  small  piece  of  work  like 
this,  clips  need  not  be  used  for  securing  the  two  halves 
during  turning ;  instead,  common  wood  screws  are  inserted 
in  the  roughly-prepared  stuff  a  little  way  beyond  the  ends 
of  the  prints,  as  illustrated  in  Fig.  243,  which  shows  the 
turned  barrel,  with  its  prints,  leaving  only  the  ends  into 
which  the  screws  are  driven  to  be  sawn  off.  The  barrel  is 
fitted  to  the  uprights  B  either  by  the  cutting-out  of  the 
latter  to  fit  the  barrel,  similarly  to  the  method  shown  at 
Figs.  240  and  241 ;  or  the  ends  of  the  uprights  may  be 
left  straight,  and  grooves  cut  across  the  barrel  to  receive 
them.  In  either  case  the  uprights  are  glued  to  the  barrel 


AND  POPPET  PATTERNS.         133 


Hollows  like  those  shown  may  be  glued  in,  strips  of  leather 
being  as  good  as  anything.  The  boss  J  may  be  fitted 
round  the  barrel  in  halves,  and  worked  to  shape  by  hand. 
The  nailing  on  of  the  boss  D  and  the  guides  E  completes 
the  pattern. 

The  poppet  shown  in  Figs.  244  to  246  is  one  of  the 
nsatest  and  stiffest  in  use  for  small  lathes.  It  must  be 
moulded  on  its  side,  and  may  be  unjointed ;  but  it  is  better 
to  joint  it  along  the  plane  D,  as  shown,  because  the  outline 


Fig.  249. 
Figs.  247  to  249.— Plain  Lathe  Poppet  Pattern. 

can  then  be  marked  off  in  the  joint  of  the  pattern.  The 
barrel  may  be  worked  by  hand  solid  with  the  body,  in 
which  case  the  beading  should  be  turned  separately,  and 
nailed  on.  Or  the  barrel  may  be  turned  and  the  body 
fitted  to  it,  as  shown,  either  by  fitting  it  to  the  curvature, 
or  by  leaving  the  top  part  of  the  body  flat  and  cutting 
out  a  portion  across  the  barrel  to  receive  it.  The  sec- 
tion across  the  centre  of  the  body  E  is  rectangular,  with 
corners  well  rounded.  The  shape  of  the  sides  in  Fig.  245 
will  be  worked  through  by  the  aid  of  a  template,  and  the 


134 


PRACTICAL  PATTERN  MAKLVG. 


angles  rounded  into  the  curved  ends,  which  are  marked 
from  the  joint  faces.  The  guide-piece  F  is  nailed  on  the 
bottom,  completing  the  pattern.  The  timber  graining 
shows  the  best  disposition  of  the  grain.  A  cross  section 
at  E  E  is  shown  below  Fig.  245. 

Fig.  247  to  249  illustrate  a  plain  poppet,  easily  made 
and  readily  fitted  up.  The  pattern  must  be  moulded  upon 
its  side,  and  should  be  jointed  in  the  plane  D  as  shown. 
The  foot  A  is  made  in  two  pieces,  less  than  the  full  width 


Fig.  250.—  Half  of  Lathe  Poppet  Pattern. 


by  the  thickness  of  the  vertical  web  B,  which  is  made 
in  two  thicknesses  and  is  glued  upon  the  feet.  At 
the  upper  part,  the  half-webs  are  recessed  a  little  way 
into  the  turned  barrel,  and  the  vertical  ribs  c  are  fitted 
between  the  foot,  the  web,  and  the  barrel.  Fig.  250  shows 
one  half  of  the  pattern,  open  on  the  joint  faces,  to  assist 
in  illustrating  the  union  of  the  different  parts,  which,  by 
a  comparison  with  the  other  figures,  will  render  everything 
clear  without  further  explanation  ;  E  indicates  the  boss 
which  provides  metal  over  the  hold-down  bolt. 


135 
CHAPTER   XII. 

SLIDE-REST    PATTERNS. 

THE  illustrations  accompanying  this  chapter  represent  the 
pattern  work  for  an  ordinary  type  of  lathe  slide-rest,  begin- 
ning with  the  saddle  and  proceeding  upwards.  The  cast- 
ings are  not  shown  separately,  but  in  the  case  of  cored 
portions  the  forms  of  the  cores,  as  they  would  appear  in  the 
castings,  are  indicated  by  means  of  dotted  lines.  This  is 
mentioned  to  avoid  confusion,  for  these  dotted  lines  have 
no  meaning  in  the  patterns  themselves  which  the  figures 
represent. 

The  saddle  pattern  is  shown  in  Figs.  251  to  255.  Fig. 
251  is  a  plan  view  as  the  casting  stands  on  the  lathe  ; 
Fig.  252  is  an  underneath  plan  showing  the  pattern  as 
it  lies  in  the  mould  ;  Fig.  253  an  end  view  at  the  front ; 
Fig.  254  an  end  view  at  the  rear ;  and  Fig.  255  a  side  view 
from  next  the  headstock. 

A  saddle  pattern  of  large  area  should  be  framed  to- 
gether in  three  pieces,  with  half  lap  joints.  Small  saddles 
of  from  12  in.  to  15  in.  in  length  can  be  cut  from  solid 
stuff,  and  the  core  prints  will  serve  to  keep  the  main 
plate  true.  The  most  suitable  disposition  of  the  grain  for 
this  mode  of  construction  is  shown  in  Figs.  251  to  255.  In 
Figs.  253,  254,  and  255  the  thickness  of  the  main  piece  is 
seen,  with  various  fittings  on  both  sides,  while  the  plan 
views  of  these  pieces  are  shown  by  Figs.  251  and  252. 
On  the  top  face  there  are  prints,  and  on  the  bottom  face 
(Fig.  252)  are  broad  facing  pieces,  which  are  planed  to 
slide  on  the  top  of  the  bed,  strips  for  the  guiding  edges, 
a  bracket  for  the  back  shaft,  and  blocks  for  the  attachment 
of  the  apron. 

In  these  figures,  A  is  the  print  for  coring  out  the  recess 
for  the  cross  traverse  or  surfacing  screw.  The  core-box 
is  shown  in  Figs.  256  and  257.  All  the  patterns  and  core- 
boxes  here  illustrated  are  to  an  exact  and  uniform  scale, 
so  that  comparisons  between  the  corresponding  dimensions 
of  prints  and  boxes  can  be  easily  made,  while  the  dotted 


136  PRACTICAL  PATTERN  MAKING. 


Fig.  251.— Plan  of  Slide-rest  Saddle  Pattern. 


SLIDE -REST  PATTERNS. 


137 


Fig.  252.— Underneath  Plan  of  Slide-rest  Saddle  Pattern. 


138 


Pit  AC  TIC  AL  PATTERN  MAKING. 


lines  before  mentioned  in  the  figures  which  indicate  the  out- 
lines of  the  cored  castings  will  further  render  the  relations 
of  core-boxes  to  patterns  and  to  castings  clear. 

The  longitudinal  and  sectional  forms  of  the  core  made 
from  the  box  (Figs.  256  and  257)  are  indicated  in  Figs. 
251,  253,  and  254.  The  box  in  Figs.  256  and  257  is  framed 
together  with  grooved  ends,  and  is  laid  upon  a  bottom 


Fig.  234. 

Fig*.  253  and  254.— Front  and  Back  End  Views  of  Slide-rest 
Saddle  Pattern; 

board.  The  sides  of  the  box  are  vertical  in  the  print  thick- 
ness, and  bevelled  below  (compare  with  Figs.  253  and  254), 
to  form  the  edges  by  which  the  cross  traverse  slide  of  the 
rest  is  guided.  The  semicircular  recess  in  which  the  sur- 
facing screw  lies,  and  the  flat  recess  in  front  to  receive  the 
nut,  are  cut  in  the  bottom  board  of  the  box.  Of  course, 
the  box  framing  is  not  fastened  to  the  bottom  board  in 
any  way,  because  that  would  prevent  delivery  of  the  core. 
It  is  simply  retained  truly  in  relation  to  the  board  by 


SLIDE- ItEST  PATTERNS. 


139 


Fijr.  257. 


140  PRACTICAL  PATTERN 


Fig.  258  and  259.— Core-box  for  Sliding  Pinion  Spindle.  Figs.  260 
to  262.— Surfacing  Slide  Pattern.  Figs.  263  and  264.— Ring  Ccrj- 
box  for  Surfacing  Slide. 


SLIDE-REST  PATTERNS.  Ul 

means  of  the  pieces  A  nailed  on  the  board,  or  by  means  of 
dowels,  the  method  being  merely  a  matter  of  choice. 

In  Figs.  251  to  255  B  and  c  show  prints  which  core  out  the 
hole  shown  dotted  in  Fig.  251,  for  the  spindle  which  makes 
the  connection  between  the  back  shaft  gear  and  the  rack 
and  pinion  sliding  movement  at  the  front.  The  enlarge- 
ment of  the  hole  next  the  print  B  is  for  the  reception  of  the 
sleeve  pinion,  which  renders  the  sliding  movement  auto- 
matic. It  is  not  necessary  to  make  the  prints  B,  c  of  the 
drop  or  pocket  form ;  round  prints  will  answer  as  well. 
In  this  case  B  will  be  nailed  on,  and  the  moulder  will  joint 
down  to  its  centre  ;  c  will  be  nailed  on  its  boss,  but  both 
together  will  be  held  with  loose  brads  as  shown,  to  be 
drawn  backwards  into  the  mould.  The  print  B  is  twice  the 
length  of  c.  The  moulder  will  thrust  the  core  endwise  into 
the  impression  of  c,  leaving  then  at  the  other  end  a  bear- 
ing surface  in  B  equal  to  half  the  length  of  B. 

A  core-box  must  be  made  for  this  in  halves,  dowelled 
together.  It  is  shown  in  plan  by  Fig.  258,  and  in  end 
view  by  Fig.  259,  one  half  having  been  removed  to  expose 
the  hole.  In  the  part  A  the  core  cuts  through  the  saddle, 
corresponding  with  the  portion  K  left  clear  of  facings  in 
Fig.  252.  The  prints  D  (Figs.  251,  253,  254,  and  255)  are 
for  tee-grooved  cores  by  which  work  is  bolted  to  the 
saddle.  A  core-box  must  also  be  made  for  these,  framed 
similarly  to  that  in  Figs.  256  and  257,  but  without  a  bottom 
board. 

The  bracket  E  for  the  back  shaft  (Figs.  251,  252,  254,  and 
255)  is  assumed  to  be  cast  on,  as  is  the  usual  practice  in 
small  lathes.  It  is  situated  rather  awkwardly  for  casting, 
being  deep  and  having  perpendicular  web  faces,  with 
bosses,  and  being  close  to  the  edge  of  the  saddle  which 
slides  along  the  rear  edge  of  the  bed.  A  clean  and 
accurate  way  to  mould  it  would  be  by  putting  a  block  print 
K  (Fig.  255)  against  one  face,  and  coring  out  that,  with  the 
bosses  included  by  the  print,  leaving  the  other  face  to  de- 
liver itself  in  the  top — the  saddle  moulding  upside  down. 
There  is,  however,  the  strip  shown  dotted  at  c,  and  this 
should  be  cast  in  order  to  lessen  planing.  But  to  do  that 
would  involve  leaving  the  bracket  E  loosely  dowelled, 
otherwise  the  edge  c  could  not  be  moulded.  But  it  is  un- 
desirable to  leave  such  brackets  loose,  because  they  are 


142 


PRACTICAL  PATTERN  HAK1XG. 


liable  to  be  rammed  out  of  truth,  and  thus  throw  the  boss 
for  the  back  shaft  out.  On  the  whole  the  best  plan  to 
adopt  is  that  shown. 

The  bracket  is  fastened  on,  and  the  edge  c  is  cast  square, 
leaving  the  V   to  be  formed  wholly  by  planing,  a  lesser 


Fig.  266. 


Fig.  267. 


Fig.  265. — Core-box  to  Form  Recess  for  Screw.     Fig.  266. — Half  Box 
Opened  in  Joint  Face.     Fig.  267. — Transverse  Section  of  Core-box. 

evil  than  having  the  bracket  cast  untrue.  But  a  print 
might  be  nailed  along  the  edge  as  at  D,  and  the  strip  cored. 
The  bosses  on  the  vertical  faces  of  the  bracket  are  both 
put  on  loosely,  as  also  is  the  one  F  through  which  the 
surfacing  screw  spindle  passes,  and  the  boss  faces  on  E 
likewise  should  be  loose  (Fig.  254).  The  moulder  then 
joints  up  to  the  centre  c,  and  half  the  bracket  delivers 


SLIDE -RES  T  PA  T  TERNS. 


143 


downwards  and  half  in  the  top.  No  holes  are  cored  in  it, 
since  that  would  be  troublesome  and  unnecessary,  be- 
cause such  holes  should  be  lined  out  and  drilled  through 
the  solid. 

The    remainder    of    the    pattern    is    self-explanatory. 
Against  the  edge  G  (Figs.  252  and  255)  the  setting-up  strip 


Fig.  2,0. 
Figs.  2JJ8  to  270.— Swivel  Slide  Pattern. 

goes.  The  faces  H  (Figs.  253  and  256)  receive  the  apron 
casting.  Such  details  will  vary  in  different  lathes,  and 
need  cause  no  difficulty.  These  blocks  or  facings  are  all 
fastened  on,  but  taper  is  given  to  the  inner  edges. 

The  pattern  of  the  surfacing  slide  is  shown  in  Figs. 
260  to  262,  with  dotted  lines  which  indicate  cored  portions. 
Fig.  260  is  a  plan,  Fig.  261  a  side  elevation,  and  Fig.  262 


144 


PRACTICAL  PATTERN  MAKING. 


an  end  elevation  ;  A  is  the  face  on  which  the  top  slide 
swivels,  and  B  is  a  ring  print  to  receive  the  core  round 
which  the  clamping  bolts  move  for  setting  the  slide  to  any 
angle  ;  c  is  a  pin  cast  with  the  slide  to  act  as  a  centre  pivot. 
The  iixode  of  construction  is  indicated  by  the  shading. 

A  core-box  (Figs.  263  and  264)  will  be  made  for  the 
print  B.  A  central  disc  and  an  outer  jointed  ring  being 
attached  to  a  bottom  board  will  form  the  annular  veed 
groove,  and  a  hole  cut  in  the  bottom  board  will  form  that 
portion  of  the  core  at  A  (Fig.  261)  through  which  the  bolts 
are  thrust.  As  the  box  is  made,  the  ring  portion  must 


Fig.  271. 
Figs.  271  and  272.— Top  Slide  Pattern. 

be  divided  and  dowelled,  to  be  withdrawn  in  halves  hori- 
zontally, on  account  of  the  undercutting  of  the  vees.  It 
is  maintained  concentrically  by  the  annulus  or  shoulder 
(see  Fig.  264).  In  a  small  slide  it  is  better  not  to  core 
this  annulus  but  to  bore  it  out  of  the  solid. 

The  portion  D  of  the  pattern  has  one  square  edge, 
against  which  the  adjustment  strip  fits,  and  a  bevelled 
edge  which  must  be  put  on  loosely,  either  with  nails  or 
with  dovetails  (Fig.  262).  The  recess  for  the  surfacing 
screw  is  cored,  E  being  the  print.  The  core-box  is  divided 
and  dowelled  (Figs.  265  to  267).  Fig.  265  shows  it  in  plan, 
Fig.  266  one  half  opened  in  the  joint  face,  and  Fig.  267 
is  a  transverse  section.  The  halves  a.re  dowelled  together, 


SLIDE-HE  ST  PATTERNS. 


145 


146  PRACTICAL  PATTERN  MAKING. 

and  the  shape  imparted  to  the  interior  for  clearing  the 
surfacing  screw  is  cut  with  chisel  and  gouge.  The  facing 
in  the  centre  of  the  box  receives  the  nut  for  the  screw. 

Figs.  268  to  270  illustrate  the  pattern  of  the  top  or 
swivel  slide.  The  construction  is  so  clearly  shown  that 
few  comments  are  necessary.  There  is  one  core  only,  a 
plain  rectangular  one  fitting  in  the  impression  of  the  print 
A,  and  the  print  moulds  downwards.  There  are  two  loose 
pieces  B,  B  tacked  or  dovetailed  on  the  body.  The  timber 
grain  shows  how  the  stuff  is  arranged.  The  top  slide  (Figs. 
271  and  272)  is  also  plain.  There  is  one  loose  strip  and  no 
coring. 

The  apron  pattern  (Figs.  273  and  274)  moulds  face  down- 
wards, as  shown  by  the  arrow  in  Fig.  274.  A  is  the  boss 
for  the  clasp-nut  spindle,  and  B  its  print  for  a  round  core  ; 
c  is  the  boss  for  the  spindle  which  operates  the  rack  pinion 
by  hand,  and  D  is  its  print ;  E,  E  are  bosses  for  the  rack 
pinion  and  intermediate  rack  pinion,  and  F  is  their  print ; 
G,  G  are  guides  for  the  clasp  nut;  H  is  a  stiffening  rib. 
The  planing  facings  wThich  match  those  on  the  saddle  must 
be  left  loose  on  the  down  side,  or  else  the  face  must  be  left 
plain  in  the  pattern. 

In  the  castings  made  from  the  patterns  various  holes 
not  shown  have  to  be  drilled.  Some  amount  of  machining 
not  indicated  in  the  patterns  also  will  be  necessary.  Some 
nuts  will  be  required,  the  patterns  for  them  being  just  like 
their  castings.  Allowances  for  tooling  are  to  be  made 
where  required  in  pattern  work  and  core-boxes  to  the 
extent  of  about  £  in. 


147 


CHAPTER  XIII. 

MISCELLANEOUS  PATTERNS  AND  CORE-BOXES. 

IN  making  patterns  for  the  screw-down  valve  shown  in 
section  and  plan  by  Figs.  275  and  276,  the  wood  for  the 
trunk  of  the  body  pattern  (Fig.  277)  is  in  two  pieces ;  fit 
them  together  and  then  glue  a  piece  of  cartridge  paper 
between.  All  the  patterns  must  be  made  in  two  pieces, 
the  joint  being  at  the  centre  line.  When  dry  the  pattern 
can  be  turned  in  the  lathe,  a  brass  or  iron  plate  being 
screwed  at  each  end  across  the  joint,  with  a  countersunk 
hole  in  the  centre  so  that  it  will  run  true. 

The  nose  of  the  valve  is  prepared  in  two  halves,  trued 
to  shape  with  the  spokeshave.  Test  it  with,  say,  four 
templates  made  of  cardboard  or  thin  zinc  cut  to  suit  the 
half  finishing  to  the  centre  line  ;  these  templates  can,  of 
course,  be  used  on  both  sides,  a  mixture  of  tripoli  and 
oil  termed  rud  being  put  on  the  edge  of  the  template, 
which,  when  applied,  leaves  a  mark  at  the  irregular  parts. 
This  process  must  be'  repeated  till  the  parts  become  quite 
true.  Then  the  nose  can  be  fixed  to  the  trunk  with  three 
dowels,  great  care  being  exercised  in  getting  it  on  true. 
A  chisel  driven  into  the  joint  will  split  the  paper,  leaving 
the  pattern  in  two  halves  as  desired. 

The  core-box  must  be  very  strong  to  withstand  the 
hammering  of  the  coremaker.  Mahogany  is  very  good 
wood  to  use,  an  extra  piece  being  glued  and  screwed  across 
the  grain  at  the  back  of  each  half.  The  two  pieces  are 
fitted  together  and  kept  in  position  with  dowels  of  brass 
and  bushes  to  suit. 

Make  the  box  to  the  outside  lines  and  begin  setting  out, 
laying  on  the  flat,  side  of  half  the  pattern  and  carefully 
lining  it  round.  Then  remove  it  and  complete  the  setting 
out  as  shown  in  Fig.  278.  Take  great  care  in  getting  the 
position  of  the  seating  A.  Minimise  the  metal  where  the 
article  does  not  require  turning,  such  as  inside  the  body 
and  below  the  seating,  as  indicated  by  the  recessed  por- 


148 


PRACTICAL  PATTERN  MAKENG. 


tions ;  of  course,  allow  extra  metal  for  turning  and  screw- 
ing where  necessary. 

When  the  core-box  is  put  together,  describe  a  circle  at 
the  top  and  bottom  end  of  a  diameter  equal  to  the  points 
c  s  (Fig.  277).  Also  cut  a  template  to  the  core  at  the 


Fig.  276. 
Figs.  275  and  276.— Vertical  Section  and  Plan  of  Screw-down  Valve. 

mouth  of  the  valve,  mark  it  on  the  core-box  and  cut  it  out, 
using  very  sharp,  thin  gouges  •for  this  purpose.  Finish 
carefully  to  the  lines  at  the  ends  and  put  on  a  thin  band 
of  the  rud  to  show  the  parts  finished.  Test  the  remainder 
of  the  semicircular  parts  with  a  square.  The  nose  part  of 


VALVE  PATTERNS  AND  CORE-BOXES. 


149 


the  core-box  is  tested  by  several  templates,  and,  after 
being  sandpapei'ed  very  smooth,  can  be  varnished  with  a ' 
mixture  of  shellac  varnish  and  gas  black. 


Fig.  277.— Body  Pattern  for  Screw-down  Valve. 

To  make  a  better  box  in  iron  or  brass,  turn  a  core  to 
the  size  and  shape  required  and  fix  the  nose  on  the  trunk. 
This  is  also  made  in  two  halves,  and  well  varnished  or 


Fig.  278.— Core-box  for  Body  for  Screw-down  Valve. 

painted  with  the  rud  and  placed  in  a  roughly-made  box 
that  holds  the  core  print  in  position.  A  quantity  of 
plaster-of-Paris  is  poured  into  the  box,  filling  it  somewhat 


150 


PRACTICAL  PATTERN  MAKING. 


above  the  centre  line  of  the  print,  and  is  allowed  to  dry. 
The  plaster  is  carefully  cut  down  to  the  centre  line,  and 
the  wood  core  print  removed,  the  sides  trimmed,  and  the 
slots  are  cut  as  shown  in  Fig.  278 ;  these  afterwards  form 


Fig.  279.— Valve-top  Cap  Tattern. 

projections  to  answer  as  dowels.  Then  the  whole  wood 
print  is  painted  with  rud  and  replaced  in  the  rough  wood 
box,  which  is  then  filled  with  plaster-of-Paris  and  allowed 
to  set.  Cut  away  all  superfluous  plaster  and  take  apart, 
leaving  a  plaster  pattern  for  the  metal  core-box.  This, 
when  thoroughly  dry,  may  be  varnished,  then  cast,  the 
shrinkage  being  sufficient  to  allow  of  the  casting  being 
cleaned  up. 

The  pattern  of  the  top  cap  or  stuffing  box  A  (Fig.  275) 


Fig.  280. — Core-box  for  Valve-top  Cap. 

is  a  plain  turning  with  a  square  formed  in  the  middle,  as 
shown  in  Fig.  279.  All  the  edges  are  slightly  taper,  and 
the  ends  slightly  rounded  for  ease  in  moulding,  c  s  being 
the  points.  The  core-box  is  illustrated  by  Fig.  280.  Where 


VALVE  PATTERNS  AND   CORE-BOXES. 


151 


the  square  comes  the  metal  is  slightly  reduced  to  lighten 
the  casting  and  to  assist  the  brass  finisher.  The  top  part 
of  the  cap  receives  packing  cotton. 

The  top  part  of  the  stuffing  nut  B  (Fig.  275)  is  made 
hexagon    shape,    the   bottom   being   round    for    screwing. 


Fig.  281.— Nut  Pattern. 


Fig.  2:>2.— Half  Core-box  for  Nut. 


The  nut  is  immersed  wholly  in  the  bottom  box  of  the 
moulder,  and  a  small  core  is  placed  as  shown  by  c  s  in 
Fig.  281,  the  half  core-box  being  shown  by  Fig.  282. 

The  spindle  c  (Fig.  275)  has  a  square  formed  on  the  top 
to  receive  the  knob  ;  the  hole  in  the  bottom  end  is  drilled 
to  receive  the  jumper  D.  The  knob  E  (Fig.  275)  is  moulded 
downwards.  The  pattern  is  turned  in  the  lathe,  and  after- 
wards cut  out  to  form  the  four  spokes.  Fig.  283  shows  the 
core  at  stays  at  A.  The  top  receives  the  pottery  plate  F 
(Fig.  275),  while  the  bottom  core  is  squared  to  fit  the 
spindle.  Fig.  284  is  a  section  through  the  core-box.  The 
jumper  is  a  plain  washer  with  a  projection  on  each  side, 
one  entering  the  drilled  spindle,  and  the  other  receiving 


Fig   283.— Knob  Pattern. 


Fig.  284.— Co.-e-box  for  Knob. 


a  nut  which  secures  the  seating  washer  w.  The  fly  or 
running  nut  G  (Fig.  275)  is  simply  a  circular  screwed  washer 
with  a  hexagon  head.  The  shrinkage  is  about  $  in.  in  the 
foot,  and  the  amount  for  turning  and  screwing  is  about 


152 


PRACTICAL  PATTERN  MAKING. 


VALVE  PATTERNS  AND   GO  RE -BOXES. 


153 


Fig.  285  is  a  face  view  of  one  half  of  the  core-box  for  a 
globe  valve  of  the  design  shown  marked,  Fig.  286  being  a 
section  on  A  B,  and  Fig.  287  a  section  on  c  D.  Two  blocks, 
being  jointed  and  dowelled,  are  squared  at  the  ends  and  on 


the  edges  where  the  branch  comes.  Centre  lines  on  the 
face  being  gauged  and  squared,  circles  are  described  on 
the  ends  and  edge  to  the  print  diameters.  The  shape  is 
scribed  round  one-half  of  the  pattern  when  laid  on  the 


PRACTICAL  PATTERN  MAKING. 


box,  and  the  thickness  of  the  metal  is  marked  within  the 
lines. 

The  semicircular  hollow  for  the  prints  is  worked  straight 
through,  and  a  shouldered  template  (Fig.  288)  is  then  used 
to  obtain  the  shape  of  the  swelled  part.  The  hollow  for 
the  branch  is  worked  from  the  edge,  the  counter-bore  of 
the  flange  being  neglected.  A  gauge  line  is  run  round 
where  the  metal  is  set  back  beyond  the  face  of  the  branch 
flange,  and  the  set-back  is  worked  down  to  template.  The 


Fig.  281). 


Fig.  290.  Fig.  292. 

Figs.  289  and  290. — Turned  Segments  for  Partitions. 
Figs.  291  and  292.— Method  of  Working  Segments. 

partition  and  valve  seat  must  be  fitted  in  four  segments, 
and  kept  loose  so  that  each  piece  may  be  withdrawn  by  a 
circular  motion  from  the  half-core  before  the  two  halves 
are  fastened  together.  Turn  these  four  segments  to  the 
shape  shown  by  Figs.  289  and  290,  holding  them  on  a  face- 
plate with  a  paper  joint.  To  tie  them  together  at  the  top, 
glue  on  four  shallow  segments  to  break  joint,  as  the  end 
joints  must  not  be  glued,  and  are,  moreover,  made  to  coin- 
cide with  transverse  lines  passing  through  the  centre  of  the 
face-plate.  Then  fit  them  into  the  body  of  the  box,  the 
binding  segments  being  cut  away. 


BULL-NOSE  PLANE  PATTERN. 


155 


A  better  way  is  to  fix  two  semicircular  templates  (Figs. 
291  and  292)  and  to  sweep  around  these  a  shouldered 
template  cut  to  the  reverse  of  Fig.  288.  A  shoulder,  ex- 
tending (say)  -^  in.  into  the  wood  and  ^  in.  below  the 
joint,  determines  the  positions  of  the  segments.  The 
other  extremity  of  each  segment  is  cut  as  in  Fig.  293,  and 
ends  are  carried  by  a  small  block  (Figs.  294  and  295)  let 
into  the  centre  of  the  box  before  being  worked  to  shape. 
This  block  makes  up  the  partition  where  it  departs  from 
the  conical  form.  Most  of  the  lines  upon  it  may  then  be 
marked  by  a  long-toothed  gauge.  Scribe  the  inclined 
dotted  lines  on  Fig.  285  when  the  section  is  marked  out 


Fig.  2'.)!.       Fig.  295. 

Fig.  203. — End  of  Segment.     Figs.  294  and  295.— Block  for  Ends  of 

Segments. 

to  assist  in  getting  the  segments  to  position.  The  end  of 
the  segment  must  agree  with  a  straightedge  placed  along 
the  line.  A  set-square  laid  in  the  semicircle  formed  by 
the  two  segments  will  test  the  correctness.  A  long-toothed 
gauge,  worked  against  the  branch  edge  of  the  box,  will 
test  the  position  of  the  valve  seat. 

One  half  of  the  box  being  worked,  the  other  is  scribed 
from  it  and  the  slant  lines  transferred.  As  each  half  of 
the  box  is  rammed  separately,  the  ends  and  the  branch 
edge  are  tapered  and  closed  by  pieces  being  screwed  up  to 
them.  The  transverse  backing,  which  all  such  boxes  should 
possess,  is  not  shown,  and  is  best  fixed  before  the  box  is 
worked. 

The  pattern  for  a  bull-nose  plane  will  be  described  as  a 
final  example.  A  lengthways  section  through  a  brass  cast- 
ing intended  for  the  body  of  a  bull-nose  plane  is  shown  by 
Fig.  296,  an  end  view  being  given  by  Fig.  297.  The  dimen- 
sion B  should  be  about  TVin-  greater  than  the  width  of  the 
wide  part  of  the  cutting  iron,  in  order  to  allow  for  filing  to 


156  PRACTICAL  PATTERN  MAKING. 

size.  The  dimension  A  is  about  ,^  in.  less  than  B.  Fig.  298 
represents  the  pattern,  the  part  exterior  to  the  contour  of 
the  casting  being  a  core-print.  The  pattern  is  made  as 
follows: — A  block  of  wood  is  planed  to  a  parallel  thickness 
equal  to  A,  and  the  whole  of  the  shape  shown  in  Fig.  298  is 


Fig.  296.  fig.  297. 

Figs.  296  and  297.— Body  of  Bull-nose  Plane. ' 

set  out  on  both  sides,  a  slight  allowance  for  draught  from 
the  sand  being  made.  The  wood  is  then  cut  to  the  outline 
of  the  figure.  Two  thin  pieces  are  then  cut  out,  both 
having  a  thickness  equal  to  half  the  difference  between 
A  and  B,  the  outline  of  these  pieces  being  similar  to  that 


Fig.  298. 
Fig.  298.— Pattern  for  Bull -nose  Plane. 

of  Fig.  298.  The  space  for  the  shaving  escapement  c 
(Fig.  296)  is  also  cut  away.  Fig.  296  shows  the  face  of  tho 
plane-  when  finished,  and  Fig.  298  shows  the  face  as  it  is 
to  be  cast.  The  difference  between  these  views  is  due  to 
allowances  for  facing  the  casting,  and  if  not  attended  to, 
an  unduly  wide  mouth  will  be  the  result.  For  castings  to 
be  made  in  iron,  it  is  advisable  to  glue  a  little  fillet  about 
3\-  in.  thick  and  |  in.  wide. over  the  part  of  the  casting 
which  is  eventually  to  become  the  mouth.  This  is  done  in 


BULL-NOSE  PLANE  PATTERN. 


157 


order  to  prevent  the  metal  being  chilled,  which  would  occur 
if  it  were  very  thin.  It  is  also  necessary  in  an  iron  casting 
to  ensure  that  the  mould  is  so  arranged  for  casting  that  the 
face  of  the  plane  occupies  its  lowest  part,  or  when  faced 
up  blow-holes  may  be  found  there.  The  core-box  (Figs. 
299  and  300)  is  made  of  two  pieces  of  wood  dowelled 
together.  After  the  blank  pieces  are  dowelled  they  are 


/"s, 


p; 

(  i 


Fig.  299. 
Figs.  £99  and  300.— Core-box  for  Bull-nose  Plane. 

planed  up  to  a  thickness  equal  to  A.  The  main  part  of 
the  pattern  is  then  laid  on  the  face  of  the  blank  core-box 
in  the  position  shown  in  Fig.  299,  and  the  shape  scribed 
on  the  core-box.  This  is  done,  of  course,  before  the  thin 
pieces  have  been  glued  on  it.  One  of  the  thin  pieces  is 
then  laid  on  the  core-box  to  fit  on  with  the  lines  already 
scribed,  and  its  shape  transferred  to  the  core-box.  That 
part  of  the  core-box  which  has  to  be  cut  away  will  then 
become  evident. 


INDEX. 


"Angling,"   or   Feather  edged   Fil- 
leting, 31,  32 
Apron  Pattern,  146 

Barrel  of  Lathe  Poppet,  131 

Bench,  Ramming,  21,  22 

Bend-pipe,  Core-box  for,  51,  52 

Blocking  Pieces,  Dowelling,  85 

Board,  Moulding,  14 

Bolt  Holes,  Searing  Iron  for,  40 

Boss,   Capstan,   Coring,  70,   71 

"  Boxing  Up,"  117 

Bracket  Casting,  Coring  Holes  In, 
71-77 

,  Double,  81,  82 

with  Slot  Holes,  79 

Brass  Pattern  Plate,  20 

,  Shrinkage  of,  11,  12 

Bull-nose  Plane  Pattern  and  Core- 
box,  155-157 

Butt  Joint,  25 

Capstan  Boss,  Coring,  70,  71 
Casting  Cylinder,  62-66 

Iron  Columns,  83-92 

Castings,  Coring  Holes  in,  59-82 

for  Hydraulic  Work,  23 

Chamber  Cores,  53 

Channels  in  Moulds.  23 

Chaplet  Nails,  66,  91 

Charcoal,  Dusting  Moulds  with,  23 

Check,  Four-part,  25,  26 

,  Three-part,  25 

Cheese-headed  Screw  Holes,   Sear- 
ing, 40 
Circular  Core-box,   50 

Patterns,  42-49 

,  Plaster,  47-49 

Columns  (see  Iron  Columns) 
Cope,   13 

Core,    Chamber,   53 

for  Iron  Column,  91 

Prints  in  Bracket  Casting  Pat- 
tern, 72 

,  Rectangular,  53-55 

,  Round,   56 

,  Stopping-over,  74 

,  Symmetrical,  56 

• ,  TTnsymmetrleal,  56 

Core-boxes,  50-58 

•,  for  Bend-pipe,  51,  52 

Bull-nose  Plane,  157 

,  Circular,     Worked    Out     with 

Set-square,   52 
for  Cylinder  Cover,  60,  61 

•—  Cylindrical  Core,  50 

—   Exhaust  Port,  97 

-   Flywheel,  56,  57 


Core-boxes  for  Gap  Lathe-bed,  1?1 

Globe  Valve,  153 

,  Internal  Flange  Fitted  to,  £2, 

for  Knob,  151 

Nut  Pattern,  151 

Screw-down  Valve,  147 

Slide-rest  Pattern,  141 

Spur  Wheel,  57 

Steam  Chest,  93 

—  Steam-engine      Cylinder, 

,  Steam-inlet,  99 

,  Steam-port,  99,  100 

for  Surfacing  Slide,  144 

Valve  Cap,  150,  151 

Coring  Gap  Lathe-beds,  117 

Hand  Capstan  Boss,  70,  71 

Holes  in  Bracket  Casting  71-77 

in  Castings,   59-82 

Cylinder  Cover,  59  62 

Stuffing-box,  68 

—  Valve-rod  Hole,  68 
Corine-out  Gap  in  Lathe-bed,  12?, 

Corner  Half-check,  24 
Curved  Fillet,  Leather  Strip  for,  33 
Cutting  Worm  Wheel  Teeth,  108 
Cylinder  Casting,  62-66 

Cover,  Core-box  for,  63,  61 

,  Coring  Holes  in,  59-62 

,  Mould  for,  61 

—   Pattern,  Steam-engine    93  100 
Cylindrical  Core-box,  50 

Dovetail  Half-check,  24 
Dowel,  29,  30 

,  Cup  and  Peg,  30 

,  Inserting,  30 

,  Peg,  29 

,  Plate,  29 

Dowelling,  28 

—  Blocking  Pieces,  85 
Drag,   13 

Eight-arm  Wheel,  Four-part  Check 

for,   25 

Exhaust  Port  Core-box,  97 
Eye-side  Frame,  17 

Filleting,  31,  32 

,  Feather-edged,  31,  32 

, ,  Strength  of,  34,  35 

Fillets,  119,  120 

- — ,  Curved,  Leather  Strip  for,  33 

,  Substitute  for,  34 

—  Worked  out  of  Flange,  33-34 

—  Worked  out  of  Solid,  33-35 


INDEX. 


Finishing  Patterns,  36  41 

Flange,  Fillet  Worked  out  of,  33,  34 

,  Internal,    fitted    into    Core 

box,  52,  53 
Flask,  13,  14 

,  Iron,  15 

,  Odd-side,  Moulding,  17 

,  Wooden,   13,   15 

Floor,  Sand,  21 

Fly-wheel,  Core-box  for,  56,  57 

Foundry  Work,  13-23 

Four-part  Check,  25,  26 

Frame,  Eye-side,  17 

— ,  Peg-side,  18 

Frames,  Moulding,  13 

Gap-lathe  Bed,  Coring,  117,  12;?,  124 

Pattern,  lib 

Gateway   Moulding,    18 
Git-hole,  Making,  23 
Glasspapering  Pattern,  36    115 
Globe  Valve  Core-box,  153 
Glue,  Objections  to,  27 
Half-check,  Corner,  21 

,  Dovetail,  24 

,  Middle,  24 

,  Ordinary,  24,  25 

Halving  Joint,  24 

Hand-turning  Lathe,  Patterns  for, 

110-124 

Headstock  Patterns,  125-130 
"  Hobbing "       Teeth         of     Worm 

Wheels,  101 
Horns     for     Back     Gear     Mandrel 

Bearings,  127,  128 
Hydraulic  Work,  Castings  for,  23 

Iron  Columns;  Casting,  83-92 

•  ,  Moulding,  83-92 

,  Patterns  for,  83-86 

Flask,  15 

• Pattern  Plate,  20 

— ,  Shrinkage  of,  11 

Joint,  Butt,  25 
,  Halving,  24 

• -,  Mitre,  25 

Jointing  Halves  of  Pattern,  104 
Jointing-up  Patterns,  24-35 
Joints  in  Pattern  Making,  24-35 
• ,  Securing,  47 

Knob  Patterns,  42,  151 

Lathe-bed,  Gap,  Coring,  117 

Pattern,   110-124 

. ,  Gap,  115 

• ,  Hand-turning,  Pattern  of,  110- 

124 
,  Headstoek  Patterns,  125-130 

Poppet,  Barrel  of,  131 

Patterns,  130-134 

Main  Pouring,  Making,  25 
Mandrel   Bearings,   Horns  for,   127, 

128 
Marking  Out  Teeth,  107,  108 


Metal  Patterns,  12 

Middle  Half-check,  24,  25 

Mitre  Joint,  25 

Mould,  Arrangement  of  Runners  in, 

22 
,  Channels  in,  23 

for  Cylinder  Cover,  61 

Denned,  10 

,  Drying,  23 

,  Dusting,  with  Charcoal,  23 

,  Loosening  Patterns  from,  18 

,  Making  Main  Pouring  in,  23 

,  Peg-side,  18 

,  Preparing,  16 

,  Sand,  13 

Moulding  Board,  14 

•    in  Foundry  Work,  16  23 

Frames,  13 

,  Gatework,  18 

Odd-side  of  Flask,  17 

,  Platework,  18-20 

Trough,  16 

Tub,  15,  16 

Nails,  Chaplet,  66,  91 
Numbering   Patterns,   36 
Nut  Pattern,  551 

,  Core-box  for,  151 

Pan,  Circular  Pattern  of,  47 
Pattern,  Glasspapering,  36 
• •,  Loosening  from  Mould,  18 

Maker,  Duties  of,  9 

,  Numbering,  36 

,  Object  of,  9 

• •  Plate,  Brass,  20 

,  Iron,  20 

,  Varnishing,  36 

Peg  Dowel,  29 

Pegs,  Steel  Plate  for  Shaping,  47 

Peg-side  Frame,  18 

Mould,  18 

Pipe  Casting,  77-79 

—  ,  Pattern   Flange   for,   77 

Plane,     Bull-nose,     Pattern     and 

Core-bos  for,  155-157 
Plaster  Patterns,  48,  149 
Plate  Dowel,  29 
Plated  Patterns,  19,  20 
Platework,  Advantages  of,  20 

,  Disadvantages  of,  20 

,  Moulding,   18-20 

Poppet  Barrel,  Turning,  132 
- — •   Patterns.  Lathe,  130-134 

,  Plain,  134 

Pouring  Metal  into  Column  Moulds, 

91,  92 

Prints,  Square,  66 
Pulleys,  Core-boxes  for,  56 

Ramming  Bench,  21.  22 
Rectangular  Core,  53-55 
Ring  Casting,  Pattern  for,  43,  44 
Round  Cores,  56 

Runners  in  Mould,  Arrangement  of, 
22 

Saddle  Pattern,  Slide-rest,  135 


ico 


INDEX. 


Sand  Floor  for  Bedding,  21 

Moulds,  13 

,  Tempering,  16 

Sawing-board,  44 

Screw-down    Valve,    Core-box    for, 
147 

,  Patterns  for,  147 

Searing,  37-41 

Bolt  Holes,  40 

Cheese-headed  Screw  Holes,  40 

Cone-headed  Screw  Holes.  40 

Iron  for  Plain  Surfaces,  37 

Strainer  Core-box,  40 

Segments,  Dog  Used  for  Tightening, 

- — -,  Making  Pattern  In,  43,  44 

,  Template  for,  44 

• ,  Tightening,  46 

,  Working,    for    Globe   Valve 

Pattern,  155 
Set-square,   Working   Out   Circular 

Core-box  -with,  52 
Shrinkage,  Allowance  for,  11,  115 

of  Brass,  11,  12 

Iron,  11 

Slide-rest  Pattern,  135-146 

• ,  Core-box  for,  141 

Saddle  Pattern,  135-146 

Slot  Holes  in  Bracket  Casting,  79 
Spindles,  43 

Spur  Wheel,  Core-box  for,  57 
Square  Prints,  66 
Steam-chest  Core-box,  98 

Pattern,  68,  69 

Steam-engine  Cylinder  Pattern,  93- 

,  Core-box  for,  96 

Steam-inlet  Core-box,  99 
Steam  port  Core-box,  99,  100 


Stopping-over  Cores,  74 

Strainer  Core-box,  Searing  Iron  for, 

40 

Strickle,  48,  49 
Stuffing-box,  Coring,  68 

Pattern,   150 

Surfacing  Slide,  Core-box  for,  144 
,  Pattern  for,  143 

Taper,  Necessity  of,  10 

Teeth,  Worm  Wheel,  Cutting,  108 

,  Marking  Out,  107,  108 

Tempering  Sand,  16 
Template  for  Segments,  44 
Three-part  Check,  25 
Trough,  Moulding,  16 
Tub,  Moulding,  15,  16 
Turned  Patterns,  42 
Turning  Poppet  Barrel,  132 

Valve  Cap  Pattern,  150 

,  Globe,  Core-box  for,   153 

,  Screw-down,  Pattern  for,   147- 

155 

Stuffing-box  Pattern,  150 

-   Top-cap  Pattern,  150 

Valve-rod  Hole,  Coring,  68 

Varnishing  Pattern,  36 

Wheel,  Eight-arm,  Four-part  Check 

for.  25,  26 
,  Marking  Out,  in  Sections,  101, 


Wooden  Flasks,  13,  15 

Worm    Wheel,    "  Hobbing "    Teeth 

of,  101 
.  Marking  Out  in  Sections, 

101,  102 
Pattern,  101-109 


PRIS-TEH  BY  CASSELI,  &  COMPANY,  LIMITED,  LA  BKI.I.E  SAUVACE,  E.G. 


ENGINEER'S  HANDY-BOOK. 

CONTAINING 

FACTS,  FORMULE,  TABLES  AND  QUESTIONS 

ON   POWER,    ITS    GENERATION,  TRANSMISSION   AND   MEASUREMENT; 
HEAT,  FUEL  AND  STEAM;   THE  STEAM-BOILER  AND  ACCESSORIES; 
STEAM-ENGINES  AND  THEIR  PARTS ;   THE  STEAM-ENGINE  IN- 
DICATOR; GAS  AND  GASOLINE  ENGINES;   MATERIALS, 
THEIR  PROPERTIES  AND  STRENGTH: 

TOGETHEE  WITH  A 

DISCUSSION  OF  THE  FUNDAMENTAL  EXPEELMENTS  IN 

ELECTRICITY, 

AND  AN   EXPLANATION  OP 

DYNAMOS,  MOTORS,  BATTERIES,  SWITCHBOARDS,  TELE- 
PHONES, BELLS,  ANNUNCIATORS,  ALARMS,  ETC., 

AND  ALSO 

RULES  FOR  CALCULATING  SIZES  OF  WIRES. 

BY 

STEPHEN   ROPER,  ENGINEER, 

AUTHOR  OF 

"  Roper's  Catechism  of  High-Pressure  or  Non-Condensing  Steam-Engines,' 
"Roper's  Hand-Book  of  the  Locomotive,''  "Roper's  Hand-Book  of 
Land  and  Marine  Engines,"  "  Roper's  Hand-Book  of  Modern 
Steam-Fire  Engines,"  "Young  Engineer's  Own  Book," 
"  Use  and  Abuse  of  the  Steam-Boiler,"  "  Ques- 
tions and  Answers  for  Engineers,"  etc. 

FIFTEENTH    EDITION. 

REVISED  AND  GREATLY  ENLARGED  BY 

EDWIN    B.   KELLER,   M.  E., 

AND 

CLAYTON    W.    PIKE,  B.  S., 

Ex-President  of  ti^e  Electrical  Section  of  the  Franklin  Institute. 


PHILADELPHIA : 
DAVIJ3    MoKAY, 

G1O  South  Washington.  Square. 
1905. 


PRICE,  POSTPAID,  $3.50.    SEND  FOR  CIRCULARS. 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 

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This  book  is  DUE  on  the  last  date  stamped  below. 


MPR  1819B2 

'•''"^ 

OCT  2  3 

OCl  21Rf 

NOV  30  1964 


MAR 


MAR  24  19651 

MAR    XX  1971 

DEC1 4     1972 

TP   ^      RFTTl 


DEC  X  X  1973 
DEC  1 


Form  L9-lCOm-9,'52(A3105)444 

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THE  LIBRARY 
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iTRUCTION. 


Important  New  Series  of  Pra  J  *  '  (  ^  .  Edited  by  PAUL  N.  HASLUCK. 
With  numerous  Illustrations  in  the  Text.  Each  book  contains  about  160  pages, 
crown  8vo.  Cloth,  $1.00  each,  postpaid. 

Practical  Draughtsmen's  Work.  '"With  226  Illustrations. 

Contents. — Drawing  Boards.  Paper  and  Mounting.  Draughtsmen's  Instruments. 
Drawing  Straight  Lines.  Drawing  Circular  Lines.  Elliptical  Curves.  Projection. 
Back  Lining  Drawings.  Scale  Drawings  and  Maps.  Colouring  Drawings.  Making  a 
Drawing.  Index. 

Practical  Gasfltting.     With  120  Illustrations. 

Contents. — How  Coal  Gas  is  Made.  Coal  Gas  from  the  Retort  to  the  Gas  Holder. 
Gas  Supply  from  Gas  Holder  to  Meter.  Laying  the  Gas  Pipe  in  the  House.  Gas 
Meters.  Gas  Burners.  Incandescent  Lights.  Gas  Fittings  in  Workshops  and  Theatres. 
Gas  Fittings  for  Festival  Illuminations.  Gas  Fires  and  Cooking  Stoves.  Index. 

Practical  Staircase  Joinery.     With  215  Illustrations. 

Contents. — Introduction:  Explanation  of  Terms.  Simple  form  of  Staircase — Housed 
String  Stair:  Measuring,  Planning,  and  Setting  Out.  Two-flight  Staircase.  Staircase 
with  Winders  at  Bottom.  Staircase  with  Winders  at  Top  and  Bottom.  Staircase  with 
Half-space  of  Winders.  Staircase  over  an  Oblique  Plan.  Staircase  with  Open  or  Cut 
Strings.  Cut  String  Staircase  with  Brackets.  Open  String  Staircase  with  Bull-nose 
Step.  Geometrical  Staircases.  Winding  Staircases.  Ships'  Staircases.  Index. 

Practical  Metal  Plate  Work.     With  247  Illustrations. 

Contents. — Materials  used  in  Metal  Plate  Work.  Geometrical  Construction  of  Plane 
Figures.  Geometrical  Construction  and  Development  of  Solid  Figures.  Tools  and 
Appliances  used  in  Metal  Plate  Work.  Soldering  and  Brazing.  Tinning.,  Re-tinning, 
and  Galvanising.  Examples  of  Practical  Metal  Plate  Work.  Examples  of  Practical 
Pattern  Drawing.  Index. 

Practical  Graining  and  Marbling.     With  79  Illustrations. 

Contents. — Graining:  Introduction,  Tools  and  Mechanical  Aids.  Graining  Grounds 
and  Graining  Colors.  Oak  Graining  in  Oil.  Oak  Graining  in  Spirit  and  Water  Colours. 
Pollard  Oak  and  Knotted  Oak  Graining.  Maple  Graining.  Mahogany  and  Pitch-pine 
Graining.  Walnut  Graining.  Fancy  Wood  Graining.  Furniture  Graining.  Imitating 
Woods  by  Staining.  Imitating  Inlaid  Woods.  Marbling:  Introduction,  Tools,  and 
Materials.  Imitating  Varieties  of  Marble.  Index. 

Painters'  Oils,  Colors  and  Varnishes.     With  Numerous  Illustrations. 

Contents. — Painters'  Oils.  Color  and  Pigments.  White  Pigments.  Blue  Pigments. 
Chrome  Pigments.  Lake  Pigments.  Green  Pigments.  Red  Pigments.  Brown  and  Black 
Pigments.  Yellow  and  Orange  Pigments.  Bronze  Colors.  Driers.  Paint  Grinding  and 
Mixing.  Gums,  Oils,  and  Solvents  for  Varnishes.  Varnish  Manufacture.  Index. 

Ready  Shortly: 
Practical  Plumbing  Work. 

Other  New  Volumes  in  Preparation. 


DAVID  McKAY,  Publisher,  Washington  Square,  Philadelphia. 


